Trazodone

Indications

Trazodone is used for: Depression, Anxiety, Insomnia, Prevention of Migraine

Adult Dose

Oral Depression Adult: Initially, 150 mg daily increased by 50-mg increments every 3-4 days up to 300-400 mg daily if necessary. Daily dosage may be given in divided doses or as a single dose at night. Max: 600 mg daily in divided doses in severely depressed patients. Elderly: Initially, 100 mg daily up to 300 mg daily. Daily dosage may be given in divided doses or as a single dose at night. Anxiety Adult: Initially, 75 mg daily increased to 300 mg daily if necessary. Daily dosage may be given in divided doses or as a single dose at night. Hepatic impairment: Severe: use with caution.

Child Dose

Renal Dose

Renal impairment: Severe: use with caution.

Administration

Should be taken with food. Take shortly after a meal or a light snack.

Contra Indications

Immediate recovery phase post MI, porphyria. Pregnancy.

Precautions

Cardiovascular disorders, epilepsy, severe hepatic or renal insufficiency. Lactation. Monitor closely during initial therapy for signs of suicide. Discontinue if signs of hepatic dysfunction, blood dyscrasias or prolonged erection. Withdraw gradually. May impair ability to drive or operate machinery.

Pregnancy-Lactation

Interactions

May diminish action of some antihypertensives (e.g. clonidine). Increased trazodone concentrations with potent CYP3A4 inhibitors such as azole antifungals, HIV-protease inhibitors and macrolides. Reduced trazodone concentrations with CYP3A4 inducers such as carbamazepine. Increased risk of excessive hypotension and hepatotoxicity with phenothiazines. Decreased anticoagulant effect of warfarin. Increased digoxin or phenytoin levels with trazodone. Increased risk of neurotoxicity, serotonin syndrome with lithium. Sedative effect enhanced by alcohol and other CNS depressants (sedatives, hypnotics, antihistamines, opioid analgesics). Potentially Fatal: Dangerous combination with MAOIs. Trazodone should not be given within 2 wk of discontinuing MAOIs and MAOIs should not be started within 1 wk of discontinuing trazodone.

Adverse Effects

Side effects of Trazodone : Drowsiness, dizziness, restlessness, confusional state, headache, nausea, vomiting, weakness, weight loss, dry mouth, constipation, diarrhoea, tremor, bradycardia or tachycardia, orthostatic hypotension, oedema, blurred vision, priapism, skin rash, syndrome of inappropriate secretion of antidiuretic hormone. Potentially Fatal: Blood dyscrasias, hepatocellular damage, neuroleptic maglignant syndrome.

Mechanism of Action

Trazodone is a triazolopyridine antidepressant which selectively inhibits serotonin re-uptake at presynaptic neurons. Unlike TCAs, peripheral re-uptake of noradrenaline is not affected. It does not have very significant antimuscarinic properties but has a marked sedative action.