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fluoxetine hydrochloride
Prozac, Prozac-20‡, Erocap‡,
Lovan‡, Zactin‡

Pregnancy Risk Category C

How supplied
Tablets:
10 mg
Pulvules:
10 mg, 20 mg
Oral solution:
20 mg/5 ml

Action
Unknown. Thought to be linked to drug's inhibition of CNS neuronal uptake of serotonin.

Indications & dosage
Depression, obsessive-compulsive disorder--

Adults:
initially, 20 mg P.O. in the morning; dosage increased based on patient response. Maximum dose is 80 mg/day.
Depression in elderly patients--

Adults ages 65 and older:
Initially, 20 mg P.O. daily in the morning. Increase dose based on response. Doses may be given b.i.d., morning and noon. Maximum dose is 80 mg/day. A lower dosage or less frequent dosing should be considered in these patients, especially those with systemic illness and those who are receiving drugs for other illnesses.
Binge-eating and vomiting behavior in patients with moderate to severe bulimia nervosa--

Adults:
60 mg P.O. in the morning.
Adjust-a-dose:
For patients with renal or hepatic impairment, a lower or less frequent dosage should be used.

Adverse reactions
CNS:
nervousness, anxiety, insomnia, headache, drowsiness, fatigue, tremor, dizziness, asthenia.
CV:
palpitations, hot flashes.
EENT:
nasal congestion, pharyngitis, cough, sinusitis.
GI:
nausea, diarrhea, dry mouth, anorexia, dyspepsia, constipation, abdominal pain, vomiting, flatulence, increased appetite.
GU:
sexual dysfunction.
Metabolic:
weight loss
Musculoskeletal:
muscle pain.
Respiratory:
upper respiratory infection, respiratory distress.
Skin:
rash, pruritus, diaphoresis.
Other:
flulike syndrome, fever.

Interactions
Drug-drug.
Carbamazepine, flecainide, vinblastine: increased serum levels of these drugs. Monitor serum levels and patient for adverse effects.
Cyproheptadine:
may reverse or decrease pharmacologic effect. Monitor patient closely.
Insulin, oral antidiabetics:
altered blood glucose levels and possible altered requirements for antidiabetic medication. Adjust dosage, as ordered.
Lithium, tricyclic antidepressants:
risk of increased adverse CNS effects. Avoid concomitant use.
Phenytoin:
increased plasma phenytoin levels and risk of toxicity. Monitor serum phenytoin levels and adjust dosage, as ordered.
Tryptophan:
increased agitation, restlessness, GI problems. Use with caution.
Warfarin, other highly protein-bound drugs:
may increase plasma levels of fluoxetine or other highly protein-bound drugs. Monitor patient closely.
Drug-lifestyle.
Alcohol use: increased CNS depression. Avoid concomitant use.

Effects on diagnostic tests
None reported.

Contraindications
Contraindicated in patients with hypersensitivity to drug and in those taking MAO inhibitors within 14 days of starting therapy. MAO inhibitors shouldn't be started within 5 weeks of stopping fluoxetine therapy.

Nursing considerations

Patient teaching

*Liquid contains alcohol. **May contain tartrazine.  †Canada  ‡Australia  §U.K.  OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING

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