Histaphen
Generic Name
Chlorpheniramine Maleate
Manufacturer
Square Pharmaceuticals Ltd.
Country
Bangladesh
Loading images...
Description
Overview of the medicine
Histaphen is an antihistamine primarily used to treat symptoms of allergic conditions such as rhinitis, urticaria, and other allergic reactions. It works by blocking histamine, a natural substance that the body produces during an allergic reaction.
Uses & Indications
Dosage
Adults
4 mg every 4-6 hours. Maximum 24 mg/day.
Elderly
Lower doses may be required, e.g., 2 mg every 4-6 hours, due to increased sensitivity to side effects and decreased renal clearance.
Renal_impairment
Caution, dose adjustment may be necessary in severe renal impairment. Consult a physician.
How to Take
For oral administration. Can be taken with or without food.
Mechanism of Action
Chlorpheniramine maleate is a first-generation antihistamine that acts as a competitive H1-receptor antagonist. It blocks the action of histamine at H1 receptors, thereby preventing or reducing histamine-mediated allergic symptoms like itching, sneezing, and watery eyes.
Pharmacokinetics
Onset
30-60 minutes
Excretion
Mainly excreted in the urine as inactive metabolites and some unchanged drug.
Half life
Approximately 12-43 hours (variable)
Absorption
Well absorbed from the gastrointestinal tract; peak plasma concentrations reached in 2-6 hours.
Metabolism
Extensively metabolized in the liver, primarily via CYP450 enzymes.
Side Effects
Contraindications
- •Hypersensitivity to chlorpheniramine or any component of the formulation
- •Newborns or premature infants
- •Nursing mothers
- •Patients with lower respiratory tract symptoms, including asthma
Drug Interactions
Alcohol
Increased central nervous system (CNS) depression.
Monoamine Oxidase Inhibitors (MAOIs)
Prolongs and intensifies the anticholinergic effects of antihistamines.
CNS depressants (e.g., sedatives, hypnotics, tranquilizers)
Additive CNS depression.
Anticholinergic drugs (e.g., tricyclic antidepressants, atropine)
Increased risk of anticholinergic side effects (e.g., dry mouth, urinary retention).
Storage
Store in a cool, dry place, below 30°C. Protect from light and moisture. Keep out of reach of children.
Overdose
Symptoms of overdose include drowsiness, CNS depression, anticholinergic effects (dry mouth, blurred vision, urinary retention), or CNS excitation (especially in children) with hallucinations, ataxia, and convulsions. Treatment is supportive and symptomatic, including gastric lavage, activated charcoal, and monitoring vital signs.
Pregnancy & Lactation
Pregnancy Category B. Use during pregnancy only if clearly needed. Not recommended for use during lactation as it may be excreted in breast milk and cause sedation in infants.
Frequently Asked Questions
Common questions about this medicine
Pack Sizes
Shelf Life
24-36 months
Availability
Pharmacies, drug stores
Approval Status
Approved by regulatory bodies worldwide (e.g., FDA, DGDA)
Patent Status
Generic; Patent expired
WHO Essential Medicine
YesAlternative Medicines in Bangladesh
Similar medicines available in the market
Global Brand Names
International brand names for this medicine
More Medicines
Explore other medicines you might be interested in
