PROZAC Fluoxetine
Use: SSRI. Depression: patients 18 years of age – Initially, 20 mg in the morning; increase dosage gradually only after a trial period of several weeks if required. Maximum: 80 mg/day. Elderly patients: 20 mg/day. Use lower or less frequent dosage in patients with renal and/or hepatic impairment and those receiving multiple medications. When switching patients to a TCA, the TCA dosage may have to be reduced and plasma TCA concentrations may need to be monitored temporarily when fluoxetine is coadministered or hs recently been discontinued. Bulimia nervosa: Adults, 60 mg/day. Assess electrolyte levels prior to starting therapy. Obsessive-compulsive disorder: 20 – 60 mg/day.
Prozac’s long-term efficacy in bulimia (i.e., > 16 weeks) and in obsessive-compulsive disorder (i.e., > 13 weeks) has not been evaluated in controlled trials.
Contraindications:
Not to be used with an MAOI or within 14 days of discontinuing MAOI therapy. Allow at least 5 weeks after stopping Prozac before starting an MAOI. Do not administer thioridazine with Prozac or within 5 weeks after Prozac has been discontinued.
Precautions:
Pregnancy, lactation, patients < 18 years of age, elderly patients. History of allergic reactions, seizures, suicidal tendency, activation of mania/hypomania, MI or unstable heart disease, diabetes, severe renal or hepatic impairment, hypokalemia (following self-induced vomiting), hyponatremia, altered platelet function.
Safety/efficacy of combined Prozac/electroconvulsive therapy not established.
Side effects:
Headache, nervousness, insomnia, drowsiness, fatigue or asthenia, anxiety, tremor, dizziness or lightheadedness, nausea, dry mouth, diarrhea, anorexia, excessive sweating. Less frequently, rash, pruritus, weight loss, sexual dysfunction, convulsions.
Interactions:
See Contraindications. Warfarin (monitor PT). Lithium levels may be increased or decreased (monitor). Use cautiously with other CNS-active drugs (e.g. tryptophan), agents highly bound to plasma protein or metabolized by the P450 2D6 system. St. John’s Wort (increase in undesirable effects).
Patient tips:
Full therapeutic effect may be delayed until 4 or 5 weeks of treatment. May cause drowsiness, dizziness (NB driving). Restrict alcohol intake.
Supplied:
10mg, 20 mg capsules; 20 mg/5 mL of mint-flavored syrup, 120 mL bottles.