An anticholinergic antiparkinson agent - It is used to treat the symptoms of an allergic reaction
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Special Alerts:
[Posted 01/17/2008] FDA informed consumers and healthcare professionals that the Agency has completed its review of information regarding the safety of over-the-counter (OTC) cough and cold medicines in children under 2 years of age and recommends that these drugs not be used to treat children in this age group because serious and potentially life-threatening side effects can occur. FDA's recommendation is based on both the review of the information the Agency received about serious side effects in children in the referenced age group and the discussion and recommendations made at the October 18 -19, 2007, public advisory committee meeting at which this issue was discussed. FDA has not completed its review of information about the safety of OTC cough and cold medicines in children 2 through 11 years of age. See the FDA Public Health Advisory for Agency recommendations regarding this issue. For more information visit the FDA website at: http://www.fda.gov/medwatch/safety/2008/safety08.htm#cough and http://www.fda.gov/cder/drug/advisory/cough_cold_2008.htm.
Adjunct to epinephrine and other standard measures for management of anaphylaxis after acute symptoms have been controlled.
Used IV or IM for management of other uncomplicated allergic conditions of the immediate type when oral therapy is impossible or contraindicated.
Allergic Rhinitis
Self-medication for temporary relief of rhinorrhea, sneezing, lacrimation, itching eyes, oronasopharyngeal irritation or itching, or cough associated with allergic rhinitis (e.g., hay fever) or other upper respiratory allergies.
Used in fixed combination with other agents (e.g., acetaminophen, phenylephrine, pseudoephedrine) for relief of rhinorrhea, sneezing, lacrimation, itching eyes, oronasopharyngeal itching, and/or other symptoms (e.g., headache, nasal/sinus congestion) associated with seasonal or perennial allergic rhinitis or other upper respiratory allergies.
Use fixed-combination preparations only when symptoms amenable to each ingredient are present concurrently.
Common Cold
Self-medication for temporary relief of symptoms associated with the common cold (e.g., rhinorrhea, sneezing, cough).
Used in fixed combination with other agents (e.g., acetaminophen, phenylephrine, pseudoephedrine) for symptomatic relief of rhinorrhea, sneezing, and/or other symptoms associated with the common cold (e.g., headache, minor aches and pains, sore throat, cough, nasal congestion).
Insomnia
Self-medication for short-term (i.e., ≤2 weeks) management of occasional sleeplessness, particularly in individuals who have difficulty falling asleep.
Used in fixed combination with other agents (e.g., acetaminophen, aspirin) for short-term management of occasional sleeplessness.
Development of tolerance reported with repeated use.
Dermatologic Disorders
Systemic antihistamines may be more effective than topical, especially if pruritus is generalized, and less likely to cause sensitivity reactions than when applied topically for pruritus associated with various dermatologic conditions.
Motion Sickness
Prevention and treatment of nausea, vomiting, and/or vertigo associated with motion sickness.
Parkinsonian Syndrome
May be useful as alternative therapy in the management of tremor early in the course of parkinsonian syndrome. Also may be useful in the management of drug-induced extrapyramidal reactions.
Used IV for management of parkinsonian syndrome when oral therapy is impossible or contraindicated. Used specifically in geriatric patients who are unable to tolerate more potent agents; for mild cases of parkinsonism in younger patients; and in combination with centrally acting anticholinergic agents in other cases of parkinsonism.
Administer diphenhydramine citrate-containing preparations orally.
Oral Administration
Diphenhydramine hydrochloride chewable tablets: Chew thoroughly before swallowing.
Diphenhydramine citrate orally disintegrating tablets: Place tablet on the tongue, allow tablet to disintegrate (within a few seconds), then swallow with or without water.
IV Administration
For solution and drug compatibility information, see Compatibility under Stability.
IV injection preferred over deep IM injection.
IV use in a home-care setting should be employed under careful supervision.
Rate of Administration
≤25 mg/minute.
Dosage
Available as diphenhydramine hydrochloride and diphenhydramine citrate; dosage is expressed in terms of diphenhydramine hydrochloride or diphenhydramine citrate.
Diphenhydramine citrate available only in fixed-combination preparations.
12.5 mg diphenhydramine hydrochloride equivalent to 19 mg diphenhydramine citrate.
Fixed-combination preparations do not permit individual titration of dosages. When used in fixed combination with other agents (e.g., acetaminophen, aspirin, phenylephrine, pseudoephedrine), select a dosage that is within the usual therapeutic range for each ingredient. Because combinations and dosage strengths vary for fixed-combination preparations, consult manufacturer's product labeling for appropriate dosage of the specific preparation.
Pediatric Patients
Allergic Conditions and the Common Cold
Acute Allergic Reactions
IV or IM
Children >1 month of age: 5 mg/kg daily or 150 mg/m2 daily (up to a maximum of 300 mg daily) divided in 4 doses.
Alternatively, 1–2 mg/kg recommended by some experts.
Allergic Rhinitis and the Common Cold
Oral
Self-medication in children 2–5 years of age: 6.25 mg every 4–6 hours (as diphenhydramine hydrochloride) or 9.5 mg every 4 hours (as diphenhydramine citrate) when directed by a clinician; do not exceed 37.5 mg (as diphenhydramine hydrochloride) or 57 mg (as diphenhydramine citrate) in 24 hours. (See Pediatric Use under Cautions.)
Self-medication in children 6–11 years of age: 12.5–25 mg every 4–6 hours (as diphenhydramine hydrochloride) or 19 mg every 4 hours (as diphenhydramine citrate); do not exceed 150 mg (as diphenhydramine hydrochloride) or 76 mg (as diphenhydramine citrate) in 24 hours.
Self-medication in children ≥12 years of age: 25–50 mg every 4–6 hours (as diphenhydramine hydrochloride) or 38 mg every 4 hours (as diphenhydramine citrate); do not exceed 300 mg (as diphenhydramine hydrochloride) or 152 mg (as diphenhydramine citrate) in 24 hours.
Insomnia
Oral
Children 2–11 years of age†: 1 mg/kg (as diphenhydramine hydrochloride) 30 minutes before retiring; do not exceed 50 mg.
Self-medication in children ≥12 years of age: 50 mg (as diphenhydramine hydrochloride) or 76 mg (as diphenhydramine citrate) at bedtime as needed, or as directed by a clinician. Higher dosages do not produce substantially greater benefit but may be associated with a higher incidence of adverse (e.g., anticholinergic) effects.
Use not recommended for ≥7–10 nights.
Motion Sickness
Oral
Children 2–5 years of age†: 6.25 mg (as diphenhydramine hydrochloride) 30–60 minutes before travel and every 4–6 hours during travel; do not exceed 37.5 mg in 24 hours.
Self-medication in children 6–11 years of age: 12.5–25 mg (as diphenhydramine hydrochloride) 30–60 minutes before travel and every 4–6 hours during travel; do not exceed 150 mg in 24 hours.
Self-medication in children ≥12 years of age: 25–50 mg (as diphenhydramine hydrochloride) 30 minutes before exposure to motion and then every 4–6 hours (before meals and at bedtime) for duration of exposure; do not exceed 300 mg in 24 hours.
IV or IM
Children >1 month of age: 5 mg/kg daily or 150 mg/m2 daily (up to a maximum of 300 mg daily) divided in 4 doses.
Parkinsonian Syndrome
IV or IM
Children >1 month of age: 5 mg/kg daily or 150 mg/m2 daily (up to a maximum of 300 mg daily) divided in 4 doses.
Adults
Allergic Conditions and the Common Cold
Acute Allergic Reactions
IV or IM
10–50 mg; in a few patients, up to 100 mg may be required.
Alternatively, 25–50 mg recommended by some experts.
Allergic Rhinitis and the Common Cold
Oral
Self-medication: 25–50 mg every 4–6 hours (as diphenhydramine hydrochloride) or 38 mg every 4 hours (as diphenhydramine citrate); do not exceed 300 mg (as diphenhydramine hydrochloride) or 152 mg (as diphenhydramine citrate) in 24 hours.
Insomnia
Oral
Self-medication: 50 mg (as diphenhydramine hydrochloride) or 76 mg (as diphenhydramine citrate) at bedtime as needed, or as directed by a clinician. Higher dosages do not produce substantially greater benefit but may be associated with a higher incidence of adverse (e.g., anticholinergic) effects.
Use not recommended for ≥7–10 nights.
Motion Sickness
Oral
Self-medication: 25–50 mg (as diphenhydramine hydrochloride) 30 minutes before exposure to motion and then every 4–6 hours (before meals and at bedtime) for duration of exposure; do not exceed 300 mg in 24 hours.
IV or IM
10–50 mg; in a few patients, up to 100 mg may be required.
Parkinsonian Syndrome
Oral
Initially, 25 mg 3 times daily (as diphenhydramine hydrochloride). If necessary, gradually increase dosage to 50 mg 4 times daily.
IV or IM
10–50 mg; in a few patients, up to 100 mg may be required.
Prescribing Limits
Pediatric Patients
Oral
Children 2–5 years of age: Maximum 37.5 mg (as diphenhydramine hydrochloride) or 57 mg (as diphenhydramine citrate) in 24 hours. (See Pediatric Use under Cautions.)
Children 6–11 years of age: Maximum 150 mg (as diphenhydramine hydrochloride) or 76 mg (as diphenhydramine citrate) in 24 hours.
Children ≥12 years of age: Maximum 300 mg (as diphenhydramine hydrochloride) or 152 mg (as diphenhydramine citrate) in 24 hours.
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