fluoxetine hydrochloride

flu·ox·e·tine hydrochloride (fl-ks-tn)

n.

An oral antidepressant chemically unrelated to other antidepressants.

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fluoxetine hydrochloride

Prozac, Prozac Weekly, Prozit (UK), Sarafem

Pharmacologic class: Selective serotonin reuptake inhibitor

Therapeutic class: Antidepressant

Pregnancy risk category B

FDA Boxed Warning

• Drug may increase risk of suicidal thinking and behavior in children and adolescents with major depressive disorder (MDD) and other psychiatric disorders, especially during first few months of therapy. Risk must be balanced with clinical need, as depression itself increases suicide risk. With patient of any age, observe closely for clinical worsening, suicidality, and unusual behavior changes when therapy begins. Advise family and caregivers to observe patient closely and communicate with prescriber as needed.
• Prozac is approved for use in pediatric patients with MDD and obsessive-compulsive disorder.

Action

Selectively inhibits serotonin reuptake in CNS; has little to no effect on norepinephrine and dopamine reuptake

Availability

Capsules: 10 mg, 20 mg, 40 mg

Capsules (delayed-release): 90 mg

Oral solution: 20 mg/5 ml

Tablets: 10 mg

⊘Indications and dosages

➣ Depression; obsessive-compulsive disorder

Adults: 20 mg/day P.O. in morning. After several weeks, may increase by 20 mg/day at weekly intervals. Give dosages above 20 mg/day in two divided doses (morning and noon); don't exceed 80 mg/day. In depression, patients stabilized on 20 mg/day may be switched to 90-mg/week delayed-release capsules (Prozac Weekly) 7 days after last 20-mg dose.

➣ Bulimia nervosa

Adults: 60 mg/day P.O.; may be titrated upward over several days

➣ Premenstrual dysphoric disorder

Adults: 20 mg/day P.O., not to exceed 80 mg/day

➣ Panic disorder

Adults: 10 mg/day P.O. for 1 week; then, if needed, increase to 20 mg/day. Dosage increases of up to 60 mg/day may be considered after several weeks if patient doesn't respond to lower dosage.

Dosage adjustment

• Hepatic impairment
• Elderly patients

Off-label uses

• Diabetic peripheral neuropathy
• Alcoholism
• Bipolar II disorder
• Borderline personality disorder
• Narcolepsy
• Posttraumatic stress disorder
• Schizophrenia
• Social phobia

Contraindications

• Hypersensitivity to drug
• MAO inhibitor use within past 14 days

Precautions

Use cautiously in:
• hepatic or renal impairment, diabetes mellitus, cardiovascular disease
• history of seizures
• pregnant or breastfeeding patients.

Administration

☞ Be aware that drug should be discontinued 5 weeks before MAO inhibitor therapy begins.
• Give before 2 P.M. to prevent nighttime insomnia.

Route	Onset	Peak	Duration
P.O.	Unknown	6-8 hr	Unknown

Adverse reactions

CNS: anxiety, drowsiness, headache, insomnia, abnormal dreams, dizziness, fatigue, nervousness, hypomania, mania, weakness, tremor, seizures, suicidal ideation

CV: chest pain, palpitations, prolonged QTc interval

EENT: visual disturbances, stuffy nose, sinusitis, pharyngitis

GI: nausea, vomiting, diarrhea, constipation, abdominal pain, dyspepsia, dry mouth, anorexia

GU: urinary frequency, sexual dysfunction, dysmenorrhea

Metabolic: hypouricemia, hypocalcemia, hyponatremia, hyperglycemia, hypoglycemia

Musculoskeletal: joint, back, or muscle pain

Respiratory: cough, upper respiratory tract infection, dyspnea, respiratory distress

Skin: diaphoresis, pruritus, erythema nodosum, flushing, rash

Other: abnormal taste, weight loss, fever, flulike symptoms, hot flashes, allergic reactions, hypersensitivity reactions

Interactions

Drug-drug . Adrenergics: increased sensitivity to adrenergics, increased risk of serotonin syndrome

Alprazolam: decreased metabolism and increased effects of alprazolam

Antihistamines, opioids, other antidepressants, sedative-hypnotics: additive CNS depression

Buspirone: potentiation of fluoxetine effects, increased risk of seizures

Carbamazepine, clozapine, digoxin, haloperidol, lithium, phenytoin, warfarin: increased blood levels of these drugs, greater risk of adverse reactions

CYP450-2D6 inducers: increased effects of these drugs

Cyproheptadine: decrease in or reversal of fluoxetine effects

Digoxin, warfarin, other highly protein-bound drugs: increased risk of adverse reactions to either drug

Efavirenz, ritonavir, saquinavir, other CYP450 inhibitors: increased risk of serotonin syndrome

MAO inhibitors: confusion, agitation, seizures, hypertension, and hyperpyrexia (serotonin syndrome)

Other antidepressants, phenothiazines, risperidone, tryptophan: increased risk of adverse reactions

Ritonavir: increased ritonavir blood level

Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, blood urea nitrogen, creatine kinase, electrolytes, glucose: increased levels

Drug-herbs. S-adenosylmethionine (SAM-e), St. John's wort: increased risk of serotonin syndrome

Drug-behaviors. Alcohol use: additive CNS depression

Patient monitoring

☞ Monitor patient for signs and symptoms of depression. Assess for suicidal ideation.
☞ Evaluate neurologic status, watching especially for seizures.
☞ Monitor cardiovascular status, particularly for prolonged QTc interval.
• Assess weight regularly. Watch for signs of eating disorders.

Patient teaching

• Encourage patient to establish effective bedtime routine to minimize sleep disorders.
• Tell patient drug may take 4 weeks or longer to be fully effective.
☞ Instruct patient to contact prescriber if he develops worsening depression or has suicidal thoughts.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• Instruct patient to minimize adverse GI effects by eating frequent, small servings of healthy food and drinking adequate fluids.
• Advise patient to discuss anti-itching medicines with prescriber if rash develops.
• Tell female patient to inform prescriber if she is pregnant or breastfeeding.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.