Adryl is an antihistamine with anticholinergic and sedative effects. It competes with histamine for H1-receptor sites on effector cells in the GI tract, blood vessels and respiratory tract.
Adryl is used for the treatment of followings:
- Seasonal, perennial, vasomotor rhinitis
- Urticaria, angioneurotic oedema, anaphylaxis
- Pruiritic conditions
- Premedication for emesis and motion sickness
- Miscellaneous like meniere's disease and parkinsonism
Adryl is also used to associated treatment for these conditions: Allergic Rhinitis (AR), Allergic cough, Allergies, Anaphylaxis, Angioedema, Common Cold, Common Cold/Flu, Conjunctival irritation, Cough, Cough Variant Asthma, Cough caused by Common Cold, Eye allergy, Fever, Insect Bites, Insect Stings, Insomnia, Irritative cough, Itching of the nose, Itching of the throat, Motion Sickness, Nasal Congestion, Oral Mucositis, Pain, Parkinsonian Syndromes, Pollen Allergy, Productive cough, Pruritus, Rash, Rhinorrhoea, Sinus Congestion, Sinus headache, Skin Irritation, Sneezing, Sunburn, Symptoms of Acute Bronchitis Accompanied by Coughing, Upper respiratory tract hypersensitivity reaction, site unspecified, Urticaria, Dermatographism, Dry cough, Watery itchy eyes, Airway secretion clearance therapy, Expectorant
|Other Names||Difenhidramina, Diphenhydramine, Diphenhydraminum|
Some prescribing information records the protein binding of diphenhydramine as approximately 78% while others have suggested the medication is about 80 to 85% bound to plasma proteins.
|Therapeutic Class||Sedating Anti-histamine|
|Manufacturer||Square Pharmaceuticals Ltd|
|Last Updated:||June 23, 2021 at 11:19 am|
Table Of contents
- Most allergic conditions: 25-50 mg three times a day with a further 50 mg at night.
- 1 to 5 years of age: 5 mg i.e., 2.5 ml of elixir 4 times a day
- More than 6 years of age: 10 mg i.e. 5 ml of elixir 4 times a day
Side effect includes sedation, dizziness, tinnitus, fatigue, ataxia, blurred vision, diplopia, euphoria, and epigastric discomfort.
Caution should be exercised with patients in whom drowsiness is undesirable e.g., drivers, machine operators. Concomitant consumption of alcohol or central nervous system (CNS) depressants will potentiate drowsiness.
Adryl administration significantly reduces the absorption of the antituberculous agent para-aminosalicyclic acid (PAS) from the gastrointestinal tract. CNS depressants may potentiate the sedative action of Adryl. Anticholinergic drugs may potentiate Adryl’s anticholinergic side effects.
- Avoid alcohol.
- Take before a meal. Take 30 minutes before a meal or 30 minutes before departure for motion sickness.
Volume of Distribution
Adryl is widely distributed throughout the body, including the CNS . Following a 50 mg oral dose of diphenhydramine, the volume of distribution is in the range of 3.3 - 6.8 l/kg .
The elimination half-life ranges from 2.4-9.3 hours in healthy adults . The terminal elimination half-life is prolonged in liver cirrhosis .
Values for plasma clearance of a 50 mg oral dose of diphenhydramine has been documented as lying in the range of 600-1300 ml/min .
Pregnancy & Breastfeeding use
Category B: There are no adequate and well controlled studies in pregnant women using diphenhydramine hydrochloride. Therefore, diphenhydramine hydrochloride should be used in pregnancy only if clearly needed. Adryl hydrochloride has been reported to be excreted in breast milk and thus, use of diphenhydramine hydrochloride in lactating mother is not recommended.
Known hypersensitivity to Adryl Hydrochloride, Ammonium chloride is contra-indicated in presence of impaired hepatic or renal function.
Symptoms: Impaired consciousness; psychosis, seizures, antimuscarinic symptoms (e.g. mydriasis, tachycardia, tachyarrhythmias), resp failure, rhabdomyolysis; acute delirium with visual and auditory hallucination (topical).
Management: Supportive and symptomatic treatment. Convulsions and marked CNS stimulation may be treated with IV diazepam.
Store between 15-30° C. Protect from moisture.