Fluoxetine (US brand name Prozac® and generic) is a selective serotonin reuptake inhibitor (SSRI). Fluoxetine as the first selective serotonin reuptake inhibitor (SSRI) to be approved by the United States Food and Drug Administration (FDA), in 1987. Now, six SSRIs are approved for use in the US.
1. Fluoxetine and its metabolite norfluoxetine are long-acting. Therefore, it usually does not cause discontinuation symptoms if it is missed for a day by mistake or when it is stopped.
2. Fluoxetine and norfluoxetine are metabolized by multiple cytochrome P450 isoenzymes — 2C9, 2C19, 2D6, and 3A4. Therefore, the total levels of fluoxetine and its active metabolites are not changed in persons who are genetically poor metabolizers on cytochrome P450 2D6.
It is a strong inhibitor of certain liver enzymes that metabolize many other medications. Therefore, it increases the levels of many other medications. That just needs to be kept in mind when either fluoxetine (Prozac) or the other drug are started or stopped.
Below is some basic information about fluoxetine.
1. Major depressive disorder (MDD): Acute and maintenance treatment
2. Obsessive-compulsive disorder (OCD): Acute and maintenance treatment
3. Bulimia nervosa: Acute and maintenance treatment
4. Panic disorder, with or without agoraphobia: Acute treatment
1. Major depressive disorder
20 mg/day in am (initial dose), 80 mg/day (maximum)
10 to 20 mg/day (initial dose)
2. Obsessive-compulsive disorder
20 mg/day in am (initial dose), 20-60 mg/ day (recommended),
80 mg/day (maximum)
a) Higher weight: 10 mg/day (initial dose), 20 mg/ day (after 2 weeks),
20-60 mg/day (recommended)
b) Lower weight: 10 mg/day (initial dose), 10-30 mg/day (recommended)
3. Bulimia nervosa
60 mg/day in the morning
4. Panic disorder
10 mg/day (initial dose), 20 mg/day (after one week), 60 mg/day (maximum)
Dosage forms and strengths (USA)
Pulvules: 10 mg, 20 mg, 40 mg
Weekly capsules: 90 mg
Liquid, Oral Solution: 20 mg/5ml. This is a clear, colorless liquid with mint flavor.
Please refer to Prescribing Information (see link below) for a complete discussion of dosage, administration, warnings and precautions, contraindications, etc.
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