Indications/Uses
Dosage/Direction for Use
Chlorphenamine Maleate Syrup is readily accepted by children and adults who prefer liquid medication. Ephedrine sulfate is an effective decongestant and bronchial relaxant-counter acts many histamine effects.
Adult 4 mg every 4-6 hours as needed (Maximum 24 mg daily).
Children 6-12 years: 2 mg every 6-8 hours a day as needed not to exceed 12 mg a day.
Or as prescribed by physician.
Overdosage
In severe overdosage the stomach should be emptied. Activated charcoal has been given as have saline laxatives. Convulsions may be controlled with diazepam or phenytoin, although it has been suggested that CNS depressants should be avoided. Other treatment is supportive and symptomatic and may include artificial respiration, external cooling for hyperpyrexia and intravenous fluids. Vasopressors such as noradrenaline or phenylephrine may be used to counteract hypotension. Forced diuresis, peritoneal dialysis or haemodialysis appear to be of limited benefit.
Administration
Contraindications
Special Precautions
Special care should be taken when using chlorphenamine maleate in children and the elderly as they are more prone to developing neurological anticholinergic effects.
Warning: May cause drowsiness. If affected do not drive or operate machinery. Avoid alcoholic drink.
If symptoms do not go away within 5 days talk to a pharmacist or doctor.
Although most antihistamines should be avoided by patients with porphyria, chlorpheniramine maleate has been used and is thought to be safe.
Adverse Reactions
Drug Interactions
The antimuscarinic effects of chlorphenamine are enhanced by other antimuscarinic drugs and both antimuscarinic and sedative effects are enhanced by monoamine oxidase inhibitors (concurrent therapy with which is contraindicated) and tricyclic antidepressants.
Metabolism of phenytoin may be inhibited by chlorpheniramine with the possible development of phenytoin toxicity.
Storage
Action
Pharmacokinetics: Chlorphenamine maleate is almost completely absorbed after administration by mouth, peak plasma concentrations occurring at about 2.5 to 6 hours. The drug is widely distributed including passage into the CNS, with a volume of distribution of between 1 and 10L/KG. About 70% of chlorphenamine in the circulation is protein-bound. Chlorpheniramine undergoes some first pass metabolism and enterohepatic recycling. Chlorphenamine is extensively metabolised, principally to inactive desmethylated metabolites which are excreted primarily in the urine, together with about 35% unchanged drug. Only trace amounts are excreted in the faeces. The mean elimination half life has been reported to be about 30 hours, with mean values ranging from 2 to 43 hours.
MedsGo Class
Features
- Chlorphenamine Maleate