Brompheniramine

Oral
Allergic conditions
Adult: 4 mg 4-6 hrly.
Child: 2-6 yr 1 mg 4-6 hrly; >6-12yr 2 mg 4-6 hrly; >12 yr Same as adult dose.

May be taken with or without food. May be taken w/ food or milk to reduce GI discomfort.

Pregnancy (3rd trimester).

Patient w/ glaucoma, prostatic hyperplasia, genitourinary obstruction, asthma, chronic bronchitis, thyroid dysfunction, CV disease (e.g. HTN, ischaemic heart disease). Childn. Pregnancy and lactation. Patient Counselling This drug may cause drowsiness and sedation, if affected, do not drive or operate machinery.

Excitability (esp in childn), drowsiness, sedation, angina pectoris, chest tightness, circulatory shock, extrasystoles, hypotension, palpitation, increased BP, tachycardia, anxiety, ataxia, chills, confusion, euphoria, fatigue, headache, hysteria, insomnia, irritability, nervousness, neuritis, paraesthesia, restlessness, seizure, tension, vertigo, diaphoresis, photosensitivity, rash, urticaria, abdominal cramps, anorexia, constipation, diarrhoea, epigastric distress, heartburn, nausea, vomiting, xerostomia, dysuria, early menstruation, urinary retention, agranulocytosis, haemolytic anaemia, thrombocytopenia, tremor, weakness, diplopia, mydriasis, blurred vision, acute labyrinthitis, tinnitus, polyuria, dry nose or throat, nasal congestion, bronchial secretions, wheezing.

May enhance the sedative effects of CNS depressants (e.g. barbiturates, anxiolytics, hypnotics, opioid analgesics, antipsychotics). Additive antimuscarinic effects w/ other antimuscarinic drugs (e.g. atropine, TCAs, MAOIs). May mask the warning signs of damage caused by ototoxic drugs (e.g. aminoglycosides).

May enhance the CNS depressant effects of alcohol.

May cause false-positive result w/ urine detection of amphetamine/methamphetamine. May interfere w/ skin tests using allergen extracts.

Brompheniramine is an antihistamine w/ antimuscarinic and moderate sedative actions. It competes w/ histamine for H₁-receptor sites on effector cells.
Absorption: Well absorbed from the GI tract. Time to peak plasma concentration: 2-4 hr.
Distribution: Widely distributed. Volume of distribution: Approx 12 L/kg. Plasma protein binding: 39-49%.
Metabolism: Undergoes N-dealkylation to form monodesmethylbrompheniramine and didesmethylbrompheniramine, and is metabolised to propionic acid derivative.
Excretion: Via urine (approx 40%, as unchanged drug and metabolites) and faeces (approx 2%). Elimination half-life: Approx 25 hr.

Oral: Store between 15-30°C. Protect from light.

Antihistamines & Antiallergics

R06AB01 - brompheniramine ; Belongs to the class of substituted alkylamines used as systemic antihistamines.