Amitriptine ( Amitriptyline ) is a tricyclic antidepressant (TCA) indicated for depressive disorders.
The safety and the effectiveness of Amitriptine ( Amitriptyline ) have not been determined with individuals below12 years of age, therefore it is not recommended at the present time for them.
Amitriptine is supplied in two forms :
- 50 mg tablet.
- 75 mg S.R. CAPSULE.
Amitriptine produced by Future for Pharmaceutical industries (FPI).
Composition
Each tablet contains: Amitriptyline .
Clinical Pharmacology
Amitriptyline is an antidepressant with sedative effect.
Amitriptyline is a tricyclic antidepressant (TCA) acts primarily as serotonin-norepinephrine reuptake inhibitor (SNRI) by blocking the serotonin transporter and the norepinephrine transporter which results in an elevation of the extracellular concentrations of these neurotransmitters and therefore an enhancement of neurotransmission .
It has been shown that facilitation of their activity has beneficial effects on the treatment of depression and anxiety.
Amitriptine Indications and Usage
Amitriptine is indicated for depressive disorders.
Dosage and Administration
The treatment should be Initiated with low dose then increased gradually .Noting carefully the clinical response and any evidence of intolerance.
When satisfactory ,improvement has been reached, the dose should be reduced to the lowest amount that will maintain relief of symptoms ,it Is appropriate to continue maintenance therapy three months or longer to lessen the possibility of relapse.
The dose preferably given at bedtime.
Initial Dose
Adult Patients
The initial dose is to begin with 50 to 100 mg then it may be increased if necessary to a total of 50 mg daily
Hospitalized patients may initially require 100 mg daily, then it may be increased gradually if necessary to 200 mg daily, a small number of hospitalized patients may need as much as 300 mg daily.
Adolescent and Elderly Patients
In general, lower doses are recommended for them or as directed by the physician .
Maintenance dose
The usual maintenance dose is 50 to 100 mg daily.
Contraindication
Amitriptine is contraindicated in patients with known hypersensitivity to Amitriptyline.
Amitriptine should not be given concomitantly with monoamine oxidase inhibitors, when it is desired to replace a monoamine oxidase inhibitor with Amitriptine, a minimum of 14 days should be allowed to elapse after the former is discontinued.
Adverse Reactions
The following adverse reactions may be observed:
Cardiovascular: Myocardial infarction, stroke, nonspecific ECG changes, heart block, arrhythmias, hypotension, syncope, hypertension, tachycardia and palpitation
CNS and Neuromuscular: Coma, seizures, hallucinations, delusions, confusion, ataxia, tremors, peripheral neuropathy, numbness, tingling, paresthesias of the extremities, dysarthria, disturbed concentration, excitement, anxiety, insomnia, nightmares, drowsiness, dizziness, weakness, fatigue, headache, syndrome of mappropriate ADH (antidiuretic hormone) secretion and tinnitus.
Anticholinergic: Paralytic ileus, hyperpyrexia, urinary retention, dilatation of the urinary tract, constipation, blurred vision, disturbance of accommodation, increased ocular pressure, mydriasis and dry mouth.
Allergic: Urticaria, photosensitization and edema of face and tongue.
Hematologic: Bone marrow depression including agranulocytosis, leukopenia, thrombocytopenia, purpura and eosinophilia.
Gastrointestinal: Nausea, vomiting, anorexia, stomatitis, peculiar taste, diarrhea, parotid swelling and rarely hepatitis (including altered liver function and jaundice).
Endocrine: Testicular swelling and gynecomastia in males, breast enlargement and galactorrhea in females, increased or decreased libido, impotence, elevation and lowering of blood sugar levels.
Other: Alopecia, edema, weight gain or loss, urinary frequency and increased perspiration.
Withdrawal Symptoms: Abrupt cessation after prolonged administration of Amitriptine may produce nausea, headache and malaise. Gradual dosage reduction has been reported to produce, within two weeks, transient symptoms including irritability, restlessness, and sleep disturbance. These symptoms are not indicative of addiction.
Drug-Drug Interaction
Drugs that inhibit the cytochrome P450 include some that are not metabolized by the enzyme (Quinidine, Cimetidine) and many that are substrates for P450 (Phenothiazines and type1C antiarrhythmics Propafenone and Flecainide).
Selective serotonin reuptake inhibitors (SSRls), Fluoxetine, Sertraline and Paroxetine, of particular importance, at least 5 weeks must elapse before initiating TCA treatment in a patient being withdrawn from Fluoxetine.
Guanethidine or similarly acting compounds, Thyroid medication, Alcohol, Barbiturates and other CNS depressants.
Anticholinergic agents .
Warnings & Precautions
Caution is advised with cardiac diseases particularly with arrhythmias, acute recovery phase following myocardial infarction, hepatic impairment (avoid if severe), pheochromocytoma, thyroid disease, history of seizures, psychoses, bipolar depression, urinary retention and angle-closure glaucoma.
All patients being treated with antidepressants for any indication should be monitored appropriately and observed closely for clinical worsening, unusual changes in behavior and suicidal ideation especially during the initial few months of a course of Amitriptine therapy or at times of dose changes either increases or decreases.
The safety and the effectiveness of Amitriptyline have not been determined with individuals below12 years of age, therefore it is not recommended at the present time for them.
Pregnancy & Lactation
Amitriptine is not recommended for pregnant women, therefore it should be used during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus.
Amitriptine is not recommended for nursing women, therefore a decision should be made whether to discontinue the nursing or discontinue the drug, taking into account the importance of the drug to the mother.
