Yoo Young


Endure Medical
Full Prescribing Info
Diphenhydramine hydrochloride.
Diphenhydramine hydrochloride is a colorless to light yellow solution.
Anticholinergic/H1 Receptor Antagonist.
Pharmacology: Diphenhydramine, a monoethanolamine derivative, is a sedating antihistamine with antimuscarinic and pronounced sedative properties.
Pharmacokinetics: Diphenhydramine HCl is widely distributed throughout the body including the CNS. It crosses the placenta and has been detected in breast milk. Diphenhydramine is highly bound to plasma proteins. Metabolism is extensive. Diphenhydramine is excreted mainly in the urine as metabolites; little is excreted as unchanged drug. The elimination half-life has been reported to range from 2.4-9.3 hrs.
Relief of allergic conditions including urticaria and angioedema, rhinitis and conjunctivitis, and in pruritic skin disorders. It is also used for antiemetic properties in the treatment of nausea and vomiting, particularly in the prevention and treatment of motion sickness and in the treatment of vertigo various causes. Diphenhydramine is used for its antimuscarinic properties in the control of Parkinsonism and drug-induced extrapyramidal disorders. Diphenhydramine has pronounced central sedative properties and may be used as a hypnotic in the short-term management of insomnia. It is a common ingredient of compound preparations for symptomatic treatment of coughs and the common cold. Diphenhydramine is used parenterally as an adjunct in the emergency treatment of anaphylactic shock.
Dosage/Direction for Use
Diphenhydramine HCl given by deep IM injection or by IV injection using concentrations of 1 or 5%. Usual doses are 10-50 mg, although doses of 100 mg have been given. No more than 400 mg should be given in 24 hrs.
Symptoms: CNS Stimulation Reaction: Tonic ataxia, tremor, delirium and convulsion.
CNS Depression Reaction: Hypnosis and coma.
Digestive: Dry mouth, anorexia, nausea and vomiting.
Cardiovascular: Hypotension.
Treatment: Immediate and appropriate measures should be instituted by counseling with a doctor or a pharmacist.
Patients with hypersensitivity to diphenhydramine HCl, asthmatic attack, pulmonary emphysema, dyspnea by chronic bronchitis, glaucoma, low urinary obstruction including prostatichypertrophy, stenoic peptic ulcer or pylorous duodenal obstruction, chromaffinoma and in patients with convulsive disease including epilepsy. Benaxil should not be administered to children <12 yrs.
Special Precautions
Special care should be given in administering diphenhydramine to patients with severe myasthenia and to patients receiving MAO inhibitors.
Benaxil should not be administered for a long time.
If insomnia continues for ≥2 weeks after administration of this drug, counseling with a doctor is needed.
Effects on the Ability to Drive or Operate Machinery: The performance of potentially hazardous tasks eg, driving a car or operation of machinery is not recommended in patients receiving diphenhydramine.
Adverse Reactions
Hypersensitivity: Eruption and fever may occur. In such cases, this drug should be discontinued.
Circulatory System: Palpitation may occur.
CNS: Sedation, drowsiness, dizziness, cenesthopathy, nervousness and headache.
Digestive: Dryness of mouth, nausea, vomiting, anorexia and diarrhea.
Optic Turbidity: Closed angle glaucoma.
Drug Interactions
Since the administration concomitant with CNS depressants, MAO inhibitors and alcohol may increase the drug interaction and the administration concomitant with anticholinergic drug may increase the anticholinergic effect, careful administration eg, reduction of dose is needed.
Store at temperatures not exceeding 30°C. Protect from light.
Shelf-Life: 36 months.
ATC Classification
R06AA02 - diphenhydramine ; Belongs to the class of aminoalkyl ethers used as systemic antihistamines.
Soln for inj (amp) 50 mg/mL x 1 mL x 10's.
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