Class: Tricyclic antidepressant (TCA)

Manufacturer: Cosmos Limited, Rangwe Rd; off Lunga Lunga Rd, Nairobi, Kenya

Dosage Form: Tablet (film coated)

Similar Brands:

Uses:

Amitriptyline is an antidepressant of the tricyclic group. It is indicated for symptoms of depressive illness especially when sedation is required.

Dosage:

Adults

Initially 50-75mg in divided doses (or as a single dose at night) increasing to 150mg daily (additional dose to be given late afternoon or evening).

Children

6-10 years: 10 to 20mg at bed time.

Over 11 years: 25 to 50mg at bed time

Side Effects:

Cardiac arrhythmias, severe hypotension and confusion may occur at high doses or in elderly patients requiring reduction of dosage. Drowsiness is not uncommon in the early stages of treatment and patients should be warned not to drive or operate machinery until it has been established that their alertness is not impaired. Other adverse effects include dry mouth, disturbances of accommodation, tachycardia, constipation and hesitancy of micturition are common early in treatment. Others include nausea, sweating, postural hypertension, dizziness, tremor, rashes, and interference with sexual function. Withdrawal symptoms which may occur on abrupt cessation of therapy include insomnia, irritability and excessive perspiration.

Warnings & Precautions:

Amitriptyline should also be used with caution in patients with a narrow angle glaucoma, urinary retention, epilepsy or recent convulsions, hepatic insufficiency and cardiovascular disorders.

Pregnancy & Lactation:

Pregnancy: only limited clinical data are available regarding exposed pregnancies. Animal studies have shown reproductive toxicity. Therefore, amitriptyline is not recommended during pregnancy unless clearly necessary and only after careful consideration of the risk/benefit.

Lactation: a risk to the suckling child cannot be excluded. A decision must be made whether to discontinue breast-feeding or to discontinue/abstain from the therapy of this medicinal product taking into account the benefit of breast feeding for the child and benefit of therapy for the women.

Drug Interactions:

Drugs that inhibit the cytochrome P450 isoenzyme CYP2D6 may produce substantial decreases in tricyclic metabolism and marked increase in plasma concentrations.  Side effects may be enhanced by the concurrent administration of antimuscarinic drugs or CNS depressants, including alcohol. Barbiturates and other enzyme inducers such as rifampicin and some antiepileptics can increase the metabolism of tricyclic antidepressants response. Cimetidine, methylphenidate, antipsychotics, and calcium-channel blockers may reduce the metabolism of the tricyclics leading to the possibility of increased plasma concentrations and accompanying toxicity.

Contraindications:

Patients with a history of myocardial infarction, arrhythmias, particularly heart block of any degree, congestive cardial failure, coronary artery insufficiency, mania, severe liver disease, hypersensitivity to any tricyclic antidepressant.

Price: Ksh 500

Notes:

Pack Size: 100s

Presentation

Amitriptyline 10mg tablets: Pink circular, biconvex, film coated tablet plain on both sides. Each film coated tablet contains: Amitriptyline 10mg, Lactose and other excipients.

Amitriptyline 10mg tablets: Pink circular, biconvex, film coated tablet embossed “C” on one side and a breakline on the other side. Each film coated tablet contains: Amitriptyline 25mg, Lactose and other excipients.

Mode of action

Amitriptyline is a trycyclic antidepressant. It is a potent inhibitor of noradrenaline re-uptake nerve endings. It is also a potent inhibitor of 5-hydroxytryptamine (Serotonin) re-uptake with equal efficacy for both mono-amines. Amitriptyline also has antagonist effects at muscarinic acetylcholine receptors and is one of the most potent tricyclic antidepressants. It blocks muscarinic cholinergic receptors in the central nervous system and in the periphery. Trycyclic antidepressants also possess affinity for muscarinic and histamine H1 receptors to varying degrees. The mechanism of action amitriptyline as an antidepressant is usually attributed to its ability to inhibit monoamine re-uptake.

Ref. No: B2123800/22.03