97-22983. Labeling of Diphenhydramine-Containing Drug Products for Over- the-Counter Human Use  

  • [Federal Register Volume 62, Number 168 (Friday, August 29, 1997)]
    [Proposed Rules]
    [Pages 45767-45774]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-22983]
    
    
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    DEPARTMENT OF HEALTH AND HUMAN SERVICES
    
    Food and Drug Administration
    
    21 CFR Parts 336, 338, 341, and 348
    
    [Docket No. 97N-0128]
    RIN 0910-AA01
    
    
    Labeling of Diphenhydramine-Containing Drug Products for Over-
    the-Counter Human Use
    
    AGENCY: Food and Drug Administration, HHS.
    
    ACTION: Notice of proposed rulemaking.
    
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    SUMMARY: The Food and Drug Administration (FDA) is proposing to amend 
    the tentative final monograph for over-the-counter (OTC) external 
    analgesic drug products, and the final monographs for oral OTC 
    diphenhydramine drug products for antiemetic, antihistamine, 
    antitussive, and nighttime sleep-aid indications. The amendment adds 
    warning statements concerning diphenhydramine toxicity. The proposed 
    warnings advise consumers not to use topical products containing 
    diphenhydramine on chicken pox, poison ivy, sunburn, large areas of the 
    body, blistered or oozing skin, more often than directed, or with any 
    other product containing diphenhydramine, even one taken by mouth, and 
    not to use oral OTC diphenhydramine products with any other product 
    containing diphenhydramine including products used topically. This 
    proposal is part of the ongoing review of OTC drug products conducted 
    by FDA.
    
    DATES: Submit written comments by November 28, 1997. FDA is proposing 
    that any final rule that may issue based on this proposal become 
    effective 12 months after the date of its publication in the Federal 
    Register.
    
    ADDRESSES: Submit written comments to the Dockets Management Branch 
    (HFA-305), Food and Drug Administration, 12420 Parklawn Dr., rm. 1-23, 
    Rockville, MD 20857.
    
    FOR FURTHER INFORMATION CONTACT: Nahid Mokhtari-Rejali, Center for Drug 
    Evaluation and Research (HFD-560), Food and Drug Administration, 5600 
    Fishers Lane, Rockville, MD 20857, 301-827-2222.
    
    SUPPLEMENTARY INFORMATION:
    
    I. Background
    
        Diphenhydramine hydrochloride is proposed for inclusion in the 
    monograph for OTC external analgesic drug products for topical use as 
    an antihistamine external analgesic.
    
    [[Page 45768]]
    
     Diphenhydramine hydrochloride is also included in the OTC drug 
    monograph for oral use as an antiemetic (21 CFR part 336). Both 
    diphenhydramine citrate and diphenhydramine hydrochloride are included 
    in OTC drug monographs for oral use as a nighttime sleep-aid (21 CFR 
    part 338), an antihistamine, or an antitussive (21 CFR part 341). The 
    various OTC advisory review panels that reviewed diphenhydramine for 
    these different uses as part of the OTC drug review did not consider 
    interactions that may occur when a person takes oral diphenhydramine 
    and applies diphenhydramine topically.
        In the Federal Register of December 4, 1979 (44 FR 69768), the 
    Advisory Review Panel on OTC Topical Analgesic, Antirheumatic, Otic, 
    Burn, and Sunburn Prevention and Treatment Drug products (the Panel) 
    evaluated the safety and effectiveness of diphenhydramine hydrochloride 
    as an antihistamine external analgesic. The Panel acknowledged that 
    diphenhydramine is absorbed through damaged skin and gains access to 
    the blood stream. However, the Panel did not consider systemic toxicity 
    from topical application to be of major importance because of its low 
    degree of toxicity when used orally or parenterally. The Panel was 
    unaware of any instance of systemic toxicity reported from topical use 
    of diphenhydramine. The Panel concluded that the drug was safe at 1- to 
    2-percent concentrations for the temporary relief of pain and itching 
    due to minor burns, sunburn, minor cuts, abrasions, insect bites, and 
    minor skin irritations. The only warning the Panel recommended was not 
    to use for longer than 7 days except under the advice and supervision 
    of a physician (44 FR 69768 at 69809).
        The agency concurred with the Panel's recommendations in the 
    tentative final monograph for OTC external analgesic drug products, 
    published in the Federal Register of February 8, 1983 (48 FR 5852). The 
    agency did not change the Panel's recommended warnings for 
    diphenhydramine, or add any other warnings.
    
    II. Developments After Publication of the External Analgesic 
    Tentative Final Monograph
    
        Since publication of the external analgesic tentative final 
    monograph, the agency has become aware of reports of adverse events 
    (toxic psychosis), especially in children, when diphenhydramine was 
    used topically for relief of pruritus due to chicken pox, poison ivy, 
    and sunburn. Some reports mentioned the concurrent use of topical 
    diphenhydramine with oral diphenhydramine drug products to relieve the 
    itch and rash associated with chicken pox. Chicken pox is not a 
    monograph indication for topical or oral diphenhydramine products.
    
    A. Early Case Reports to FDA
    
        The agency has reviewed case reports of toxic psychosis reported to 
    its Spontaneous Reporting System for the period from 1979 to 1989 (Ref. 
    1).
        In 1979, a 6-year-old boy developed chicken pox and was treated 
    with baking soda baths (8 ounce (oz)/tub) every 2 hours followed by 
    topical application of a lotion containing 1 percent diphenhydramine 
    and calamine every 2 hours. Twelve hours later he developed unusual 
    behavior (talking to imaginary people, playing with imaginary toys, did 
    not recognize parents). On the third day, a doctor saw the child and 
    prescribed diphenhydramine elixir every 4 hours. After 2 doses, the boy 
    became agitated and his strange ideas became worse. He was hospitalized 
    with hallucinations, bizarre inappropriate behavior, and disorientation 
    to time and place. He was afebrile. His pupils were dilated and his 
    face was flushed. Diphenhydramine in calamine and diphenhydramine 
    elixir were suspected of causing the toxic psychosis. The child was 
    given no medication and the following morning he was fully alert and 
    his behavior was normal, without hallucinations or delusions.
        In 1980, a physician reported that diphenhydramine from a 1 percent 
    diphenhydramine-calamine lotion was absorbed in high concentrations in 
    two patients who were afebrile in the late stages of chicken pox. The 
    first patient had diphenhydramine lotion painted on the body and sealed 
    with a dryer by his mother. The patient developed hallucinations and 
    delirium. A second patient who had the same lotion applied but not 
    sealed also developed hallucinations. The physician noted that 
    hallucinations and delirium would not be expected in the late stages of 
    this disease.
        In 1987, an 8-year-old child was admitted to the hospital for 
    severe psychosis, urinary retention, ataxia, bizarre posturing, and 
    dilated pupils. During the 12 hours before admission, 1 percent 
    diphenhydramine-calamine lotion was applied three different times on 
    the child from head to toe for severe poison ivy contact dermatitis. A 
    toxic drug screen was negative for diphenhydramine but revealed traces 
    of benzodiazepine which the child might have ingested. No other 
    medication was given. The diphenhydramine lotion was removed and the 
    child recovered fully.
        In 1989, a pharmacist reported that his 6-year-old son experienced 
    toxic psychoses (hyperactive, jittery, disoriented with visual 
    hallucinations) within 24 hours of application of 1 percent 
    diphenhydramine-calamine lotion to chicken pox lesions. Diphenhydramine 
    elixir was given 2 days before and on the day of the topical 
    application. The child was hospitalized, treated with activated 
    charcoal, and recovered completely within 24 hours, with no further 
    problems.
    
    B. Early Pediatric Literature
    
        Patranella (Ref. 2) reported an incident where a 4-year-old boy 
    became toxic after topical application of 3 oz of 1 percent 
    diphenhydramine-calamine lotion to chicken pox rash. The child was 
    admitted to the hospital because of increasing hyperactivity, irregular 
    eye movements, hallucinations, and intermittently failing to recognize 
    his parents. The rash developed the day before admission, 16 days after 
    exposure to varicella. The child's pupils were 4 millimeters in 
    diameter and reacted sluggishly to light. He was awake, disoriented to 
    person and place, combative, ataxic, and displayed tongue rolling. A 
    urine drug screen revealed the presence of diphenhydramine. The lotion 
    was washed from his skin with water and his mental status returned to 
    normal within 6 to 8 hours. The report noted that diphenhydramine is a 
    histamine (H1) receptor blocker which can cause central 
    nervous system excitation or sedation. The fatal dose in adults is 20 
    to 40 milligrams/kilogram (mg/kg). The 4-year-old boy received 50 mg/kg 
    topically over a 6-hour period.
        Filloux (Ref. 3) described a 9-year-old boy with chicken pox who 
    had 1 percent diphenhydramine-calamine lotion applied liberally from 
    head to toe, a total of 12 oz in 48 hours, for intense pruritus. 
    Diphenhydramine toxicity resulted with organic psychosis masquerading 
    as varicella encephalitis, a serious neurologic complication of 
    varicella zoster (chicken pox) disease that can result in permanent 
    neurologic sequelae or death. On admission to the emergency room, the 
    boy was markedly agitated, frightened, disoriented, completely 
    confused, having frequent visual and auditory hallucinations, and would 
    assume bizarre postures. Pupils were dilated but reactive. Laboratory 
    results were within normal limits. The serum toxic screen showed a 
    diphenhydramine level of 1.4 micrograms per milliliter (g/mL), 
    which exceeded the therapeutic level of 0.3 g/mL. No further 
    diphenhydramine
    
    [[Page 45769]]
    
    lotion was applied. Although agitated and hallucinating through the 
    night, the following morning he was calmer, but still confused. His 
    diphenhydramine level had dropped to 0.7 g/mL. He was lucid by 
    noon and by 4 p.m. his diphenhydramine level was 0.6 g/mL. He 
    was discharged from the hospital with a normal mental status. Ample 
    evidence in this patient confirmed that transdermal absorption of 
    diphenhydramine resulted in intoxication and organic psychosis. The 
    report advised that appropriate caution was warranted when treating 
    pruritus with topical antihistamine preparations, particularly when 
    substantial epidermal breakdown exists.
        Tomlinson, Helfaer, and Wiedermann (Ref. 4) described a case of 
    diphenhydramine toxicity mimicking varicella encephalitis. Physical 
    examination disclosed evidence of diphenhydramine toxicity related to 
    systemic absorption of a topical preparation. The patient, a 5-year-old 
    girl, developed chicken pox rash 4 days before admission to the 
    hospital. Her mother had applied 1 percent diphenhydramine-calamine 
    lotion repeatedly over most of the child's body during this 4-day-
    period, but gave no other medications. The day before admission the 
    child appeared agitated, did not sleep, had an unsteady gait, and had 
    trembling of the extremities. Later, she developed visual 
    hallucinations and her speech became unintelligible. Upon admission to 
    the hospital, she was disoriented, agitated, and grasping at imaginary 
    objects in the air. Neurologic examination revealed dilated pupils, 
    flushed face, and ataxia. A urine toxicity screen was positive only for 
    diphenhydramine. The child's status improved quickly after the 
    diphenhydramine lotion was removed. No other therapy was given and she 
    was discharged on the fourth day. A followup examination done 2 weeks 
    later was normal.
        Although initially believed to have varicella encephalitis, the 
    child's symptoms (ataxia, hallucinations, mydriasis, and flushing of 
    the face) were more suggestive of an anticholinergic reaction. Tests 
    confirmed diphenhydramine toxicity rather than varicella encephalitis. 
    The report concurred with one manufacturer's recommendations that 
    diphenhydramine not be used in skin disorders, such as varicella, where 
    extensive systemic absorption of topical preparations may occur. The 
    report suggested that families of children with chicken pox be warned 
    to be cautious in the use of this drug product.
        Schunk and Svendsen (Ref. 5) reported on three children (ages 4, 5, 
    and 7) with chicken pox who developed toxic encephalopathy from having 
    been treated with both oral and topical diphenhydramine. All displayed 
    some of the symptoms common to diphenhydramine toxicity: Dilated 
    pupils, flushed face, agitation, confusion, hallucinations, and ataxic 
    gait. The plasma diphenhydramine level was 1.5 g/mL in the 4-
    year-old and 0.96 g/mL in the 5-year-old. After discontinuing 
    the diphenhydramine, all children displayed normal mental status.
        This report advised that physicians should be alerted to the 
    possibility of diphenhydramine toxicity when confronted with a child 
    with varicella and acute mental status changes. Further, both families 
    and physicians should be advised against combined use of topical and 
    oral diphenhydramine-containing preparations.
        Woodward and Baldassano (Ref. 6) described a case of 
    diphenhydramine intoxication from the combined effects of oral 
    diphenhydramine elixir and topical diphenhydramine-calamine lotion in a 
    5-year-old boy who developed chicken pox 3 days before being taken to 
    the emergency room. He had been treated with 6 or 7 teaspoons of oral 
    diphenhydramine (12.5 mg/5 mL) for a total dosage of 75 to 87 mg (over 
    36 hours). His mother also had applied 1 percent diphenhydramine-
    calamine lotion liberally over his body in a 12-hour period, 24 hours 
    prior to presentation in the emergency department. The boy's behavior 
    was bizarre; he was talking to and seeing objects and people that were 
    not present. The boy had the classic symptoms of diphenhydramine 
    toxicity, including hallucinations, tachycardia, and dilated pupils. A 
    toxic screen showed both acetaminophen and diphenhydramine (1.94/
    g/L approximately 14 hours after the last oral dose). All 
    diphenhydramine was discontinued, and the child returned to normal the 
    next day. Varicella encephalitis was ruled out. The report stated that 
    children more often show excitation with overdosage of antihistamines 
    than the usual sedative effect seen in adults.
        The article further stated that data on percutaneous absorption of 
    diphenhydramine are limited. The recommended oral dose is 5 mg/kg/24 
    hours and three to four applications of topical diphenhydramine lotion 
    per day. The child had a total of 3.6 mg/kg/36 hours, or less, of oral 
    diphenhydramine, less than half the daily recommended dosage, and a 
    larger amount of lotion over a 12-hour period. Therefore, absorption of 
    the lotion appears to have been a primary factor in the adverse 
    reaction. The report noted that toxicity from oral use is more common 
    than toxicity from topical use of diphenhydramine. Fatalities have been 
    reported in both children and adults from oral overdosage. However, no 
    deaths have been reported from topical diphenhydramine use alone. The 
    report advised that physicians and patients need to be aware of this 
    potential toxicity.
    
    C. More Recent Case Reports
    
        Between 1987 and 1990, a major manufacturer of OTC diphenhydramine 
    drug products received four adverse event reports that described toxic 
    psychoses in seven children (Ref. 7). Apparently the drug products were 
    being misused, contrary to labeling, and were being applied to large 
    areas of the body where there was broken skin, possibly causing 
    increased systemic absorption. Based on these seven cases, the 
    manufacturer voluntarily revised the label warnings for its topical 
    products containing diphenhydramine. In 1989, the manufacturer added to 
    the following products a warning not to use on chicken pox and measles 
    unless supervised by a doctor: A cream and lotion product containing 1 
    percent diphenhydramine and 8 percent calamine, and a cream and spray 
    product containing 1 percent diphenhydramine and 0.1 percent zinc 
    acetate. In 1990, the manufacturer added to these products a second 
    warning not to use any other drugs containing diphenhydramine while 
    using the topical products. This warning was added based on reports 
    that the topical diphenhydramine drug products were being used with 
    oral diphenhydramine drug products to relieve the itch and rash 
    associated with chicken pox and measles, possibly resulting in toxic 
    serum diphenhydramine levels. In April 1993, the manufacturer 
    reformulated its lotion and cream products containing 1 percent 
    diphenhydramine and 8 percent calamine to replace the diphenhydramine 
    with 1 percent pramoxine hydrochloride.
        Summaries of the adverse event reports received by the manufacturer 
    follow:
        The first report involved a 7-year-old boy who developed chicken 
    pox. Oral hydroxyzine hydrochloride (one dose at 6:30 p.m.) was 
    prescribed. The child's mother applied 5 to 10 mL of 1 percent 
    diphenhydramine-calamine lotion three times to the child's abdomen and 
    chest between 7:45 and 11:30 p.m. Around 12
    
    [[Page 45770]]
    
    a.m., the child became confused, irritable, and began hallucinating. 
    When hospitalized, his diphenhydramine level at 5:40 a.m. was 73 
    nanograms per mL (ng/mL) (the normal level is 25 to 40 ng/mL). The 
    diphenhydramine-calamine lotion was removed from the skin and the child 
    recovered uneventfully the next day.
        The second report involved four children, ages 4 to 6 years, who 
    developed chicken pox. Typically, the mothers applied 1 percent 
    diphenhydramine-calamine lotion over an extensive area of the body 
    three to four times daily. In one case, the child was concurrently 
    receiving diphenhydramine syrup. In all cases, within 24 to 48 hours, 
    the children became irritable, delirious, and began hallucinating. The 
    children were treated in an emergency room by washing the 
    diphenhydramine lotion from their bodies, and they responded within 24 
    to 36 hours.
        The third report concerned a 9-year-old boy with a mild sunburn 
    without broken or blistered skin. An hour after his mother liberally 
    applied one-half of a 45-gram tube of 1 percent diphenhydramine-
    calamine cream to the boy's trunk and limbs, he developed increased 
    tiredness and became confused and disoriented. He convulsed, with 
    widespread muscular twitching and ``rolling of the eyes'' 1\1/2\ to 2 
    hours after the cream had been applied. He was taken to the hospital 
    and a chemical toxicology screen revealed a diphenhydramine level of 60 
    ng/mL. The child was treated with activated charcoal and intravenous 
    fluids. Approximately 32 hours later, the diphenhydramine level was 16 
    ng/mL; the child recovered uneventfully and was discharged the 
    following day.
        The fourth report described an 8-year-old boy with a history of 
    allergies and asthma who developed extensive chicken pox. One percent 
    diphenhydramine-calamine lotion was applied all over the body every 4 
    to 5 hours for approximately 48 hours. The child complained of blurred 
    vision and ``not being able to see clearly'' on the second day after 
    ``breaking out.'' He received acetaminophen every 4 to 5 hours for 
    fever. About 2 to 3 a.m., the child awoke with hallucinations of flying 
    insects. A dose of acetaminophen and a teaspoon of diphenhydramine 
    elixir were given, and additional diphenhydramine-calamine lotion was 
    applied. Afterwards, the boy's body was twitching, he was restless and 
    unable to sit still or sleep. On the advice of the local emergency 
    room's personnel, the child was placed in a cool tub of water to lower 
    his temperature (103 to 104  deg.F). Although his temperature was 
    reduced, the boy continued to hallucinate. After another application of 
    diphenhydramine-calamine lotion, the child was taken to the hospital 
    around 7 a.m., still hallucinating. Neurological tests and a test for 
    Reye's syndrome were negative, and the child was sent home. Another 
    dose of diphenhydramine-calamine lotion was applied at 11 a.m. and 
    after 1 to 2 hours the child began to bump into a hallway wall and was 
    unable to sit still. The last dose of diphenhydramine lotion was 
    applied mid-afternoon. A few hours later, the boy fell asleep for 4 
    hours, awoke vomiting, and had difficulty breathing. After these 
    problems subsided, the child recovered uneventfully.
        In the last 6 years, FDA has received several additional reports of 
    toxic psychoses as a result of topical application of diphenhydramine. 
    One doctor reported two cases in children who had symptoms of delirium 
    from absorption of diphenhydramine from a 1 percent diphenhydramine-
    calamine product applied to their bodies (Ref. 8). One child had a 
    blood level of 0.31 g/mL while the other child's blood level 
    was drawn much later and was not indicative of a toxic level. The 
    doctor expressed concern about the potential side effects of the 
    diphenhydramine in this product.
        Chan and Wallender (Ref. 9) reported three cases of diphenhydramine 
    toxicity. Two of the cases were included in earlier articles discussed 
    previously. The third case described a 2-year-old boy who developed 
    chicken pox lesions over his body. He was given an unknown amount of 
    diphenhydramine elixir every 3 to 4 hours, and a 1 percent 
    diphenhydramine-calamine in a lotion and/or spray was applied topically 
    to most of his body surface. The child became increasingly irritable 
    and displayed inappropriate behavior. The parents contacted the 
    emergency room and were instructed to bathe the child to remove the 
    diphenhydramine lotion. However, the child continued to have 
    inappropriate behavior and visual hallucinations, and was brought to 
    the emergency room 4 hours later. Vital signs were temperature 37.1 
    deg.C (rectally), heart rate 124 beats per minute, and respiration 36 
    breaths per minute. Chicken pox lesions covered his body and, although 
    he had brief periods of inappropriate behavior, he was able to follow 
    simple commands. The serum diphenhydramine concentration was 1.5 
    g/mL. Based on laboratory reports, diphenhydramine 
    concentrations greater than 0.1 g/mL are potentially toxic. 
    After 2 hours of observation, the boy was dismissed. He was alert and 
    playful without evidence of toxicity during a follow-up examination 
    later that morning.
        The report noted that the topical diphenhydramine products used in 
    treating the patients discussed in the article had a label warning 
    against use in chicken pox unless supervised by a physician. According 
    to the authors, cases described in the article demonstrated three 
    important points. First, absorption of topically applied 
    diphenhydramine in patients with chicken pox and possibly other skin 
    disorders with extensive disruption of the skin barrier can occur, 
    resulting in serious systemic toxicity. Second, the use of topically 
    applied diphenhydramine products in this patient population should be 
    discouraged. Finally, pharmacists should educate the public as well as 
    health professionals regarding the potential toxicity of these easily 
    accessible diphenhydramine-containing nonprescription medications.
        McGann et al. (Ref. 10) reported a case of a 19-month-old girl who 
    developed chicken pox 5 days before being brought to the clinic. The 
    girl had been treated with acetaminophen for fever, colloidal oatmeal 
    baths, 1 percent diphenhydramine-calamine lotion applied to her entire 
    body three or four times a day, and syrup given in varying doses 
    totaling approximately 50 mg of diphenhydramine. Two hours later, the 
    child began behaving strangely and rolling her eyes back into her head.
        When brought to the clinic, the child was awake but did not 
    interact with the examiner. She was moderately agitated and frightened; 
    would not respond to commands; had a wide-eyed stare; had widely 
    dilated pupils that were sluggishly reactive to light; occasionally 
    made grimacing, tongue-chewing, and lip-smacking motions; staggered 
    when walking; and retained urine. Her serum diphenhydramine level was 
    1,948 ng/mL. The girl was bathed to remove the diphenhydramine, then 
    admitted to the hospital for hydration, cardiac monitoring, bladder 
    catheterization for urine retention, and observation. After 48 hours, 
    she had returned to normal and was discharged from the hospital.
        The report cautioned parents to refrain from using topical 
    diphenhydramine to avoid a serious life-threatening drug toxicity, and 
    noted that the drug label specifically warns against use for chicken 
    pox and measles, except under the supervision of a physician. The 
    agency notes that the labeling directions proposed in Sec. 348.50(d) of 
    the tentative final monograph for OTC external analgesic
    
    [[Page 45771]]
    
    drug products (48 FR 5852 at 5869) state that a doctor should be 
    consulted for children under 2 years of age. The report did not 
    indicate whether a doctor had prescribed the drug.
    
    III. The Agency's Tentative Conclusions and Proposal
    
        The case reports described a number of adverse events resulting 
    from topical application of diphenhydramine to large areas of the body, 
    often where there was broken skin and, in some cases, concurrent use of 
    topical and oral diphenhydramine products. The diphenhydramine products 
    were used to relieve pain and itching due to chicken pox (most cases), 
    poison ivy (1 case), and sunburn (1 case). The age range of the 
    patients with reactions was 19 months to 9 years. The symptoms 
    determined to be most suggestive of diphenhydramine toxicity included 
    dilated pupils, flushed face, hallucinations, ataxic gait, and urinary 
    retention. As the Panel noted (44 FR 69768 at 69809), diphenhydramine 
    is absorbed through damaged skin, and the case reports confirmed that 
    transdermal absorption occurs. In some cases, high serum concentrations 
    confirmed diphenhydramine toxicity. Symptoms gradually disappeared when 
    diphenhydramine was removed from the body by bathing and oral 
    administration of diphenhydramine was discontinued. Most patients 
    returned to normal in about 48 hours after the drug was withdrawn. No 
    deaths have been reported from topical diphenhydramine use alone.
        The authors of many of these reports have indicated the need to 
    inform health professionals and consumers about the situations when 
    topical diphenhydramine should not be used, especially in conjunction 
    with oral diphenhydramine. This is especially true in patients with 
    chicken pox and possibly other skin disorders with extensive disruption 
    of the skin barrier, which can result in serious systemic toxicity if 
    absorption of diphenhydramine occurs. As noted in section II.C. of this 
    document, a major manufacturer of OTC diphenhydramine drug products 
    voluntarily added warning information to the labeling of its topical 
    products.
        The agency believes there is underreporting of adverse reactions 
    for topical diphenhydramine drug products. There is currently no 
    adverse event reporting requirement for topical diphenhydramine 
    products included in an OTC drug monograph. In addition, the agency is 
    concerned that consumers, primarily parents, may use these topical 
    products casually because they consider them to be innocuous. Because 
    the exact extent of the problem is not known, and there is a 
    potentially large exposure of the general population to this 
    ingredient, the agency has determined that additional warnings are 
    needed to avoid the possibility of serious adverse reactions. A 
    sufficient number of significant serious neuropsychiatric events have 
    already occurred (especially in children) to propose a change in the 
    labeled warnings for both topical and oral diphenhydramine products. In 
    this document, the agency is proposing to require the following 
    additional warning for topical products containing diphenhydramine: 
    ``Do Not Use'' (these three words in bold print) ``on chicken pox, 
    poison ivy, sunburn, large areas of the body, broken, blistered, or 
    oozing skin, more often than directed, or with any other product 
    containing diphenhydramine, even one taken by mouth.''
        The agency notes that one manufacturer includes ``not to use on 
    measles'' in the warning that it voluntarily added to its topical 
    diphenhydramine products. However, because none of the case reports 
    were associated with measles lesions, the agency has not specifically 
    listed measles in the warning. The agency invites interested persons to 
    submit any available information related to any adverse events 
    associated with the topical application of diphenhydramine to measles.
        Manufacturers may use bullet points or other identifying marks to 
    emphasize the subparts of this warning. The format of this warning 
    might look something like the following:
        Do Not Use (these words in bold print):
         on chicken pox, poison ivy, sunburn
         on large areas of the body
         on broken, blistered, or oozing skin
         more often than directed
         with any other product containing diphenhydramine, even 
    one taken by mouth
        The agency is proposing this warning in new Sec. 348.50(c)(10) 
    under the heading For products containing diphenhydramine hydrochloride 
    identified in Sec. 348.10(c)(1). For these products, this warning shall 
    be the first statement under the heading ``Warnings:''
        In addition, in Secs. 336.50, 338.50, 341.72, and 341.74 the agency 
    is proposing an additional warning for oral drug products that contain 
    diphenhydramine. The warning states: ``Do Not Use'' (these three words 
    in bold print) ``with any other product containing diphenhydramine, 
    including one applied topically.'' The agency believes that this 
    warning statement will help reduce the toxicity that may occur from the 
    inadvertent concurrent use of several products containing 
    diphenhydramine. The agency points out that its recent final rule/
    enforcement policy that provides for diphenhydramine citrate or 
    diphenhydramine hydrochloride to be labeled for concurrent 
    antihistamine and antitussive use should also help reduce the toxicity 
    that may occur from the concurrent administration of more than one oral 
    product containing diphenhydramine. (See the Federal Register of April 
    9, 1996 (61 FR 15700).)
        Manufacturers of OTC topical and oral diphenhydramine drug products 
    are encouraged to implement this labeling addition voluntarily as soon 
    as possible after publication of this proposal, subject to the 
    possibility that FDA may change the wording of the warning statement as 
    a result of comments filed in response to this proposal. Because FDA is 
    encouraging the voluntary use of the proposed additional warning 
    statement at this time, the agency advises that manufacturers will be 
    given ample time after publication of a final rule to use up any 
    labeling voluntarily implemented in conformance with this proposal.
    
    IV. References
    
        The following references have been placed on display in the Dockets 
    Management Branch (address above) and may be seen by interested persons 
    between 9 a.m. and 4 p.m., Monday through Friday.
        (1) Drug Experience Reports No. 801101-034-00101, 
    80051000100501, 8706110020071, 89081500100012, 89081500100011, OTC 
    Vol. 06DTFM, Docket No. 78N-0301, Dockets Management Branch.
        (2) Patranella, P., ``Diphenhydramine Toxicity Due to Topical 
    Application of Caladryl,'' Clinical Pediatrics, 3:163, 1986.
        (3) Filloux, F., ``Toxic Encephalopathy Caused by Topically 
    Applied Diphenhydramine,'' The Journal of Pediatrics, 108:1018-1020, 
    1986.
        (4) Tomlinson, G., M. Helfaer, and B. Wiedermann, 
    ``Diphenhydramine Toxicity Mimicking Varicella Encephalitis,'' The 
    Pediatric Infectious Disease Journal, 6:220-221, 1987.
        (5) Schunk, J. E., and D. Svendsen, ``Diphenhydramine Toxicity 
    from Combined Oral and Topical Use,'' The Pediatric Forum, 142:1020-
    1021, 1988.
        (6) Woodward, G. A., and R. N. Baldassano, ``Topical 
    Diphenhydramine Toxicity in a Five-Year Old with Varicella,'' 
    Pediatric Emergency Care, 4:18-20, 1988.
        (7) Letter dated December 14, 1993, from R. G. Kohler, Warner 
    Lambert Co. to W. E. Gilbertson, FDA, in OTC Vol. 06DTFM, Docket No. 
    78N-0301, Dockets Management Branch.
    
    [[Page 45772]]
    
        (8) Drug Experience Report No. 698132, OTC Vol. 06DTFM, Docket 
    No. 78N-0301, Dockets Management Branch.
        (9) Chan, C. Y. J., and K. A. Wallander, ``Diphenhydramine 
    Toxicity in Three Children with Varicella-Zoster Infection,'' The 
    Annals of Pharmacology, 25:130-132, 1991.
        (10) McGann, K. P. et al., ``Diphenhydramine Toxicity in a Child 
    with Varicella,'' A Case Report, The Journal of Family Practice, 
    35:210-214, 1992.
    
    V. Analysis of Impacts
    
        FDA has examined the impacts of the proposed rule under Executive 
    Order 12866 and the Regulatory Flexibility Act (5 U.S.C. 601-612). 
    Executive Order 12866 directs agencies to assess all costs and benefits 
    of available regulatory alternatives and, when regulation is necessary, 
    to select regulatory approaches that maximize net benefits (including 
    potential economic, environmental, public health and safety, and other 
    advantages; distributive impacts; and equity). Under the Regulatory 
    Flexibility Act, if a rule has a significant economic impact on a 
    substantial number of small entities, an agency must analyze regulatory 
    options that would minimize any significant economic impact of a rule 
    on small entities.
        Title II of the Unfunded Mandates Reform Act (21 U.S.C. 1501 et 
    seq.) requires that agencies prepare a written statement and economic 
    analysis before proposing any rule that may result in an expenditure in 
    any 1 year by State, local, and tribal governments, in the aggregate, 
    or by the private sector, of $100 million (adjusted annually for 
    inflation).
        The agency believes that this proposed rule is consistent with the 
    principles set out in the Executive Order and in these two statutes. 
    The purpose of this proposed rule is to add warning statements to the 
    labeling of oral and topical OTC drug products that contain 
    diphenhydramine. These warning statements concern diphenhydramine 
    toxicity and are intended to help ensure the safe and effective use of 
    all OTC drug products that contain this ingredient. Potential benefits 
    include reduced toxicity when consumers use these products.
        This proposed rule amends the final monographs for oral OTC 
    diphenhydramine drug products for antiemetic, antihistamine, 
    antitussive, and nighttime sleep-aid indications and will require some 
    relabeling of these products to add the new warning statement. The 
    proposed rule also amends the tentative final monograph for OTC 
    external analgesic drug products and will require some relabeling to 
    add the new warning statement to products containing diphenhydramine. 
    The agency's drug listing system identifies approximately 100 
    manufacturers and 300 marketers of over 800 oral OTC diphenhydramine 
    drug products, and 10 manufacturers and 50 marketers of over 100 
    topical OTC diphenhydramine drug products. It is likely that there are 
    some additional marketers and products that are not currently included 
    in the agency's system. However, after adjusting for overlap among the 
    oral and external counts, the agency estimates that there are a total 
    of 100 manufacturers and 300 marketers of about 1,000 affected stock 
    keeping units (SKU) (individual products, packages, and sizes).
        The agency has been informed that relabeling costs of this type 
    generally average about $2,000 to $3,000 per SKU. Assuming that there 
    are about 1,000 affected OTC SKU's in the marketplace, total one-time 
    costs of relabeling would be $2 to $3 million. The agency believes that 
    actual costs would be lower for several reasons. First, most of the 
    label changes will be made by private label manufacturers that tend to 
    use relatively simple and less expensive labeling. Second, for oral OTC 
    diphenhydramine drug products, the agency is proposing a 12-month 
    implementation period that would allow many manufacturers to coordinate 
    this change with routinely scheduled label printing and/or revisions. 
    Similarly, labeling changes for external OTC diphenhydramine drug 
    products would not be required until that monograph is issued and 
    becomes final. Thus, the relabeling costs for a warning statement on 
    these products would be mitigated or eliminated. In addition, because 
    the new warning statement involves only a single sentence, 
    supplementary labeling (e.g., stick on labeling) could be used for 
    those oral products not undergoing a new labeling printing within this 
    1-year period.
         The proposed rule would not require any new reporting and 
    recordkeeping activities. Therefore, no additional professional skills 
    are needed. There are no other Federal rules that duplicate, overlap, 
    or conflict with the proposed rule. The agency does not believe that 
    there are any significant alternatives to the proposed rule that would 
    adequately provide for the safe and effective OTC use of drug products 
    that contain diphenhydramine.
        This proposed rule may have a significant economic impact on some 
    small entities. The labeling of many of the affected products is 
    prepared by private label manufacturers for small marketers. Census 
    data provide aggregate industry statistics on the total number of 
    manufacturers for Standardized Industrial Classification Code 2834 
    Pharmaceutical Preparations by establishment size, but do not 
    distinguish between manufacturers of prescription and OTC drug 
    products. According to the U.S. Small Business Administration (SBA) 
    designations for this industry, over 92 percent of the roughly 700 
    establishments and over 87 percent of the 650 firms are small. (Because 
    census size categories do not correspond to the SBA designation of 750 
    employees, these figures are based on 500 employees.)
        An analysis of IMS Co. listings for manufacturers of OTC drug 
    products found that from 46 to 69 percent of the 400 listed firms are 
    small using the SBA definition of 750 employees. The agency's drug 
    listing system indicates that about 300 marketers will need to relabel, 
    and that this relabeling will be prepared by about 100 entities, most 
    of which are private label manufacturers. Thus, the agency believes 
    that most of the manufacturers affected by this proposed rule would be 
    small.
        Because this regulation would affect the information content of all 
    OTC drug products that contain diphenhydramine, firms that manufacture 
    or relabel these OTC drug products will need to change the information 
    panel for each affected SKU. Some of these costs of doing so will be 
    mitigated because the agency is allowing up to 1 year for oral products 
    so that the required labeling revision may be made in the normal course 
    of business. Labeling changes for topical products may be coordinated 
    with the final monograph for OTC external analgesic drug products. 
    Among the steps the agency is taking to minimize the impact on small 
    entities are: (1) To provide enough time for implementation to enable 
    entities to use up existing labeling stock, and (2) to provide for the 
    use of supplementary labeling (e.g., stick on labeling) if necessary. 
    The agency believes that these actions provide substantial flexibility 
    and reductions in cost for small entities.
        The agency considered but rejected several labeling alternatives: 
    (1) Voluntary relabeling, (2) a longer implementation period, and (3) 
    an exemption from coverage for small entities. The agency does not 
    consider any of these approaches acceptable because they do not assure 
    that consumers will have the most recent needed information for safe 
    and effective use of OTC diphenhydramine drug products at the earliest 
    possible time.
    
    [[Page 45773]]
    
        This analysis shows that this proposed rule is not economically 
    significant under Executive Order 12866 and that the agency has 
    undertaken important steps to reduce the burden to small entities. 
    Nevertheless, some entities, especially those private label 
    manufacturers that provide labeling for a number of the affected 
    products, may incur significant impacts. Thus, this economic analysis, 
    together with other relevant sections of this document, serves as the 
    agency's initial regulatory flexibility analysis, as required under the 
    Regulatory Flexibility Act. Finally, this analysis shows that the 
    Unfunded Mandates Act does not apply to the proposed rule because it 
    would not result in an expenditure in any 1 year by State, local, and 
    tribal governments, in the aggregate, or by the private sector, of $100 
    million.
        The agency invites public comment regarding any economic impact 
    that this rulemaking would have on manufacturers of OTC oral and 
    topical drug products containing diphenhydramine hydrochloride. 
    Comments regarding the economic impact of this rulemaking on such 
    manufacturers should be accompanied by appropriate documentation. The 
    agency is providing a period of 90 days from the date of publication of 
    this proposed rulemaking in the Federal Register for comments on this 
    subject to be developed and submitted. The agency will evaluate any 
    comments and supporting data that are received and will reassess the 
    economic impact of this rulemaking in the preamble to the final rule.
    
    VI. Paperwork Reduction Act of 1995
    
        FDA tentatively concludes that the labeling requirements proposed 
    in this document for oral and topical OTC drug products are not subject 
    to review by the Office of Management and Budget because they do not 
    constitute a ``collection of information'' under the Paperwork 
    Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Rather, the proposed 
    warning statements are a ``public disclosure of information originally 
    supplied by the Federal government to the recipient for the purpose of 
    disclosure to the public'' (5 CFR 1320.3(c)(2)).
    
    VII. Environmental Impact
    
        The agency has determined under 21 CFR 25.24(c)(6) that this action 
    is of a type that does not individually or cumulatively have a 
    significant effect on the human environment. Therefore, neither an 
    environmental assessment nor an environmental impact statement is 
    required.
    
    VIII. Request for Comments
    
        Interested persons may, on or before November 28, 1997, submit 
    written comments on the proposed regulations to the Dockets Management 
    Branch (address above). Written comments on the agency's economic 
    impact determination may be submitted on or before November 28, 1997. 
    Three copies of all comments are to be submitted, except that 
    individuals may submit one copy. Comments are to be identified with the 
    docket number found in brackets in the heading of this document and may 
    be accompanied by a supporting memorandum or brief. Received comments 
    may be seen in the office above between 9 a.m. and 4 p.m., Monday 
    through Friday.
    
    List of Subjects in 21 CFR Parts 336, 338, 341, 348
    
        Labeling, Over-the-counter drugs.
    
        Therefore, under the Federal Food, Drug, and Cosmetic Act and under 
    authority delegated to the Commissioner of Food and Drugs, it is 
    proposed that 21 CFR parts 336, 338, and 341, and 21 CFR part 348 (as 
    proposed in the Federal Register of February 8, 1983 (48 FR 5852)) be 
    amended as follows:
    
    PART 336--ANTIEMETIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE
    
        1. The authority citation for 21 CFR part 336 continues to read as 
    follows:
    
        Authority: Secs. 201, 501, 502, 503, 505, 510, 701 of the 
    Federal Food, Drug, and Cosmetic Act (21 U.S.C. 321, 351, 352, 353, 
    355, 360, 371).
    
        2. Section 336.50 is amended by adding new paragraph (c)(8) to read 
    as follows:
    
    Sec. 336.50  Labeling of antiemetic drug products.
    
    * * * * *
        (c) * * *
        (8) For products containing diphenhydramine hydrochloride 
    identified in Sec. 336.10(c). ``Do Not Use'' (these three words in bold 
    print) ``with any other product containing diphenhydramine, including 
    one applied topically.''
    * * * * *
    
    PART 338--NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER 
    HUMAN USE
    
        3. The authority citation for 21 CFR part 338 continues to read as 
    follows:
    
        Authority: Secs. 201, 501, 502, 503, 505, 510, 701 of the 
    Federal Food, Drug, and Cosmetic Act (21 U.S.C. 321, 351, 352, 353, 
    355, 360, 371).
    
        4. Section 338.50 is amended by adding new paragraph (c)(5) to read 
    as follows:
    
    Sec. 338.50  Labeling of nighttime sleep-aid drug products.
    
    * * * * *
        (c) * * *
        (5) ``Do Not Use'' (these three words in bold print) ``with any 
    other product containing diphenhydramine, including one applied 
    topically.''
    * * * * *
    
    PART 341--COLD, COUGH, ALLERGY, BRONCHODILATOR, AND ANTIASTHMATIC 
    DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE
    
        5. The authority citation for 21 CFR part 341 continues to read as 
    follows:
    
        Authority: Secs. 201, 501, 502, 503, 505, 510, 701 of the 
    Federal Food, Drug, and Cosmetic Act (21 U.S.C. 321, 351, 352, 353, 
    355, 360, 371).
    
        6. Section 341.72 is amended by adding new paragraphs (c)(6)(iv) 
    and (c)(7) to read as follows:
    
    Sec. 341.72  Labeling of antihistamine drug products.
    
    * * * * *
        (c) * * *
        (6) * * *
        (iv) For products containing diphenhydramine citrate or 
    diphenhydramine hydrochloride identified in Sec. 341.12(f) and (g). 
    ``Do Not Use'' (these three words in bold print) ``with any other 
    product containing diphenhydramine, including one applied topically.''
        (7) For products containing diphenhydramine citrate or 
    diphenhydramine hydrochloride identified in Sec. 341.12(f) and (g). 
    ``Do Not Use:'' (these three words in bold print) ``with any other 
    product containing diphenhydramine, including one applied topically.''
    * * * * *
        7. Section 341.74 is amended by adding new paragraphs 
    (c)(4)(viii)(C) and (c)(4)(ix)(C) to read as follows:
    
    Sec. 341.74  Labeling of antitussive drug products.
    
    * * * * *
        (c) * * *
        (4) * * *
        (viii) * * *
        (C) ``Do Not Use'' (these three words in bold print) ``with any 
    other product containing diphenhydramine, including one applied 
    topically.''
        (ix) * * *
        (C) ``Do Not Use'' (these three words in bold print) ``with any 
    other product
    
    [[Page 45774]]
    
    containing diphenhydramine, including one applied topically.''
    * * * * *
    
    PART 348--EXTERNAL ANALGESIC DRUG PRODUCTS FOR OVER-THE-COUNTER 
    HUMAN USE
    
        8. The authority citation for 21 CFR part 348 continues to read as 
    follows:
    
        Authority: Secs. 201, 501, 502, 503, 505, 510, 701 of the 
    Federal Food, Drug, and Cosmetic Act (21 U.S.C. 321, 351, 352, 353, 
    355, 360, 371).
    
        9. Section 348.50 (as proposed at 48 FR 5852, February 8, 1983) is 
    amended by adding new paragraph (c)(10) to read as follows:
    
    Sec. 348.50  Labeling of external analgesic drug products.
    
    * * * * *
        (c) * * *
        (10) For products containing diphenhydramine hydrochloride 
    identified in Sec. 348.10(c)(1). The following statement shall appear 
    as the first warning statement under the heading ``Warnings:'' ``Do Not 
    Use:'' (these three words in bold print) ``on chicken pox, poison ivy, 
    sunburn, large areas of the body, broken, blistered, or oozing skin, 
    more often than directed, or with any other product containing 
    diphenhydramine, even one taken by mouth.''
    * * * * *
    
        Dated: August 22, 1997.
    William B. Schultz,
    Deputy Commissioner for Policy.
    [FR Doc. 97-22983 Filed 8-28-97; 8:45 am]
    BILLING CODE 4160-01-F
    
    
    

Document Information

Published:
08/29/1997
Department:
Food and Drug Administration
Entry Type:
Proposed Rule
Action:
Notice of proposed rulemaking.
Document Number:
97-22983
Dates:
Submit written comments by November 28, 1997. FDA is proposing that any final rule that may issue based on this proposal become effective 12 months after the date of its publication in the Federal Register.
Pages:
45767-45774 (8 pages)
Docket Numbers:
Docket No. 97N-0128
RINs:
0910-AA01: Over-the-Counter (OTC) Drug Review
RIN Links:
https://www.federalregister.gov/regulations/0910-AA01/over-the-counter-otc-drug-review
PDF File:
97-22983.pdf
CFR: (5)
21 CFR 336.50
21 CFR 338.50
21 CFR 341.72
21 CFR 341.74
21 CFR 348.50