Dental: Symptomatic relief of allergic symptoms caused by histamine release which include nasal allergies and allergic dermatosis; also to produce local anesthesia through infiltration of mucous membranes Medical: Symptomatic relief of allergic symptoms caused by histamine release which include nasal allergies and allergic dermatosis;

can be used for mild nighttime sedation; prevention of motion sickness and as an antitussive; has antinauseant and topical anesthetic properties; treatment of phenothiazine-induced dystonic reactions

Use with caution in patients with angle-closure glaucoma, peptic ulcer, urinary tract obstruction, hyperthyroidism; some preparations contain sodium bisulfite; syrup contains alcohol; diphenhydramine has high sedative and anticholinergic properties, so it may not be considered the antihistamine of choice for prolonged use in the elderly

Hypersensitivity to diphenhydramine or any component; should not be used in acute attacks of asthma

>10%: Central nervous system: Slight to moderate drowsiness Respiratory: Thickening of bronchial secretions
1% to 10%: Central nervous system: Headache, fatigue, nervousness Gastrointestinal: Nausea, vomiting, diarrhea, abdominal pain, xerostomia, appetite increase, weight gain, dry mucous membranes Neuromuscular & skeletal: Arthralgia
Respiratory: Pharyngitis

Increased toxicity: CNS depressants worsens CNS and respiratory depression, monoamine oxidase inhibitors may increase anticholinergic effects; syrup should not be given to patients taking drugs that can cause disulfiram reactions (ie, metronidazole, chlorpropamide) due to high alcohol content

Over Dose / Poisoning : Symptoms of overdose include CNS stimulation or depression; overdose may result in death in infants and children

There is no specific treatment for an antihistamine overdose, however, most of its clinical toxicity is due to anticholinergic effects. Anticholinesterase inhibitors (eg, physostigmine, neostigmine, pyridostigmine, or edrophonium) may be useful by reducing acetylcholinesterase. For anticholinergic overdose with severe life-threatening symptoms, physostigmine 1-2 mg (0.5 mg or 0.02 mg/kg for children) I.V., slowly may be given to reverse these effects.

Children: Oral: (>10 kg): 12.5-25 mg 3-4 times/day; maximum daily dose: 300 mg I.M., I.V.: 5 mg/kg/day or 150 mg/m2/day in divided doses every 6-8 hours, not to exceed 300 mg/day
Adults: Oral: 25-50 mg every 6-8 hours Nighttime sleep aid: 50 mg at bedtime I.M., I.V.: 10-50 mg in a single dose every 2-4 hours, not to exceed 400 mg/day Topical: For external application, not longer than 7 days

Take as directed; do not exceed recommended dose. Avoid use of other depressants, alcohol, or sleep-inducing medications unless approved by prescriber. You may experience drowsiness or dizziness (use caution when driving or engaging in tasks requiring alertness until response to drug is known);

or dry mouth, nausea, or vomiting (frequent small meals, frequent mouth care, chewing gum, or sucking hard candy may help). Report persistent sedation, confusion, or agitation; changes in urinary pattern; blurred vision; sore throat, difficulty breathing, or expectorating (thick secretions); or lack of improvement or worsening or condition. Breast-feeding precautions: Do not breast-feed.