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trademark for preparations of fluoxetine hydrochloride, an antidepressant.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

fluoxetine hydrochloride

Prozac, Prozac Weekly, Prozit (UK), Sarafem

Pharmacologic class: Selective serotonin reuptake inhibitor

Therapeutic class: Antidepressant

Pregnancy risk category B


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


Capsules: 10 mg, 15 mg, 20 mg, 40 mg

Capsules (delayed-release): 90 mg

Oral solution: 20 mg/5 ml

Tablets: 10 mg, 15 mg, 20 mg

Indications and dosages

Major depressive disorder (MDD)

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. 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.

Children ages 8 to 18: Initially, 10 to 20 mg/day P.O. After 1 week at 10 mg daily, dosage should be increased to 20 mg/day. However, because of higher plasma levels in lower-weight children, starting and target dose in this group may be 10 mg/day. Dosage increase to 20 mg/day may be considered after several weeks if insufficient clinical improvement occurs.

Obsessive-compulsive disorder (OCD)

Adults: Initially, 20 mg/day P.O. in morning. After several weeks, may increase dosage. Give doses above 20 mg/day once daily (morning) or in two divided doses b.i.d. (morning and noon). Dosage range of 20 to 60 mg/day is recommended; however, dosages of up to 80 mg/day have been well tolerated. Don't exceed 80 mg/day.

Children ages 7 to 17: Initially, 10 mg/day P.O. in morning in adolescents and higher-weight children; after 2 weeks, may increase dosage to 20 mg/day. Additional dosage increases may be considered after several more weeks if insufficient clinical improvement occurs. Dosage range of 20 to 60 mg/day is recommended. Initially, 10 mg/day P.O. in lower-weight children; may increase dosage after several more weeks if insufficient clinical improvement occurs. Dosage range of 20 to 30 mg/day is recommended. Experience with daily doses greater than 20 mg is very minimal; there is no experience with doses greater than 60 mg.

Acute treatment of depressive episodes associated with bipolar I disorder

Adults: Initially, 20 mg fluoxetine P.O. with 5 mg olanzapine P.O. daily; dosage range of fluoxetine is 20 to 50 mg; olanzapine, 5 to 12.5 mg. Safety of fluoxetine doses above 75 mg and olanzapine doses above 18 mg haven't been established

Bulimia nervosa

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

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.

Premenstrual dysphoric disorder

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

Dosage adjustment

• Hepatic impairment

• Concurrent disease or multiple concomitant medications

• Pregnant women during third trimester

• Elderly patients

Off-label uses

• Diabetic peripheral neuropathy

• Alcoholism

• Bipolar II disorder

• Borderline personality disorder

• Narcolepsy

• Posttraumatic stress disorder

• Schizophrenia

• Social phobia


• Hypersensitivity to drug

• MAO inhibitor use within past 14 days

• Concurrent use of thioridazine or within 5 weeks of discontinuing fluoxetine

• Concurrent use of pimozide


Use cautiously in:

• hepatic or renal impairment, diabetes mellitus, cardiovascular disease, concomitant illness, acute narrow-angle glaucoma

• history of seizures, serotonin syndrome or neuroleptic malignant syndrome, clinical worsening and suicidal thinking and behavior, activation of mania or hypomania

• hyponatremia in association with syndrome of inappropriate antidiuretic hormone secretion

• concurrent use of NSAIDs, aspirin, warfarin, or other drugs that affect coagulation

• concurrent use of tryptophan (use not recommended)

• pregnant patients (third trimester)

• breastfeeding patients (use not recommended)

• children younger than age 7 (in OCD use), younger than age 8 (in MDD use), younger than age 18 for all other uses (safety and efficacy not established).


Be aware that drug should be discontinued 5 weeks before MAO inhibitor or thioridazine therapy begins.

• Give before 2 P.M. to prevent nighttime insomnia.

• Be aware that drug should be gradually reduced rather than abruptly stopped whenever possible.

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, serotonin syndrome, neuroleptic malignant syndrome (NMS), allergic reactions, hypersensitivity reactions


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

Aspirin, NSAIDs, warfarin, other drugs that affect coagulation: increased risk of GI or other bleeding

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: serotonergics, triptans: increased risk of serotonin syndrome

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

Pimozide: increased risk of drug interaction or QTc-interval prolongation

Thioridazine: increased risk of QTc-interval prolongation or potential for elevated thioridazine plasma level

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

Sodium: decreased level

Drug-herbs. 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.

Monitor patient for signs and symptoms of allergic reactions, serotonin syndrome, or NMS-like reactions. Discontinue drug immediately and initiate supportive treatment if these reactions occur.

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.

Instruct patient to immediately stop drug and report signs and symptoms of allergic reactions (rash), serotonin syndrome, or neuroleptic malignant syndrome-like reactions.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• 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.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


A trademark for the hydrochloride salt of the drug fluoxetine.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Fluoxetine Neuropharmacology An oral selective serotonin reuptake inhibitor–SSRI used for depression, obsessive-compulsive disorder, bulimia nervosa Adverse effects 10-15% of Pts experience anxiety, nervousness, insomnia, weight loss, overstimulation, upset stomach, headache Contraindications MAOI therapy. See SSRI–serotonin-selective reuptake inhibitor.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


A brand name for FLUOXETINE. This widely used mood-controlling drug can interact dangerously with drugs of the MAO inhibitor group and some other antidepressants.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
In 1994, some of the relatives of the victims of a man who carried out a workplace shooting - who had been put on Prozac a month before - brought a civil suit against Eli Lilly.
The public has a right to know what's in our water supplies and whether they are inadvertently taking drugs like Prozac.'
A spokesman for US-based Prozac manufacturers, Eli Lilly and Co, agreed, saying they didn't support online sales of the drug.
As Peter Kramer's 1993 bestseller Listening to Prozac describes so compellingly, many even celebrate the "new self" that cosmetic psychopharmacology seems to make possible.
Diane Cassidy, for example, was prescribed Prozac not for depression but for "off label" use as a weight-loss drug.
Zuellig Pharma said that after taking the above-mentioned factors into an actuarial analysis, it was notified by Eli Lily Taiwan, the owner of Prozac, to cease production on April 1 and withdraw the product from the Taiwan market.
Researchers from the Department of Pharmacology, Nippon Medical School, showed that chronic treatment of adult mice with fluoxetine (Prozac) caused changes to granule cells, one of the main types of neuronal cells inside the hippocampus, and to their connections with other neuronal cells.
The pounds 30-a-month drug agomelatine, also known as Valdoxan, was found to help 77.7 per cent of people with severe depression compared with 68.8 per cent on Prozac.
The pounds 30-a-month drug agomelatine (Valdoxan) was found to help 77.7% of people with severe depression compared with 68.8% on Prozac, a study comparing the drugs found.
Speaking during yesterday's hearing, consultant psychiatrist Dr Stephen Humphries said increased serotonin as a result of the large Prozac dose could have worsened Mr Walker's anxiety.
Over the following weeks, I realized the many questions I should have asked the doctor and the answers he should have provided before prescribing Prozac. Why do I need this medication?

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