Zhejiang Ruixin


Global Pharmatrade
Full Prescribing Info
Diphenhydramine hydrochloride.
Each mL contains: Diphenhydramine Hydrochloride 50 mg.
Pharmacology: Diphenhydramine, a monoethanolamine derivative, is a sedating antihistamine with antimuscarinic and pronounced sedative properties.
Pharmacokinetics: Diphenhydramine Hydrochloride 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 to 9.3 hours.
Diphenhydramine is used for the relief of allergic conditions including urticaria and angioedema, rhinitis and conjunctivitis, and in pruritic skin disorders. It is also used for its antiemetic properties in the treatment of nausea and vomiting, particularly in the prevention and treatment of motion sickness, and in the treatment of vertigo with 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 is given by deep intramuscular injection or by intravenous injection using concentrations of 1% or 5%. Usual doses are 10 to 50 mg, although doses of 100 mg have been given. No more than 400 mg should be given in 24 hours.
Or as prescribed by a physician.
Overdose of this drug may cause the following 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.
In these cases, immediate and appropriate measures should be instituted by a doctor or a pharmacist.
Diphenhydramine is contraindicated in patients with hypersensitivity to the drug. It should not be administered to patients with asthmatic attack, pulmonary emphysema, and dyspnoea by chronic bronchitis, glaucoma, and lower urinary tract obstruction including prostatic hypertropy. It is also contraindicated inpatients with stenoic peptic ulcer or pylorous duodenal obstruction, and chromaffinoma. Diphenhydramine is also contraindicated in patients with convulsive disease including epilepsy. It should not be administered to children under 12 years.
Special Precautions
Special care should be given in administering Diphenhydramine to patients with severe myasthenia gravis and to patients receiving MAO inhibitors.
The drug should not be administered for a long time.
If insomnia continues for 2 weeks or more after administration of this drug, counseling with a doctor is needed.
The performance of potentially hazardous tasks such as 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 concomitant administration with CNS depressants, MAO inhibitors and alcohol may increase the drug interaction therefore careful administration such as reduction of a dose is needed.
The anticholinergic effect of Diphenhydramine might also increase with concomitant administration of anticholinergic drug therefore careful administration such as reduction of a dose is also needed.
Store at temperatures not exceeding 30°C. Protect from light.
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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