Fluoxetine is an oral drug that is used for treating depression. It is in a class of drugs called selective serotonin reuptake inhibitors (SSRIs), a class that also contains citalopram (Celexa), paroxetine (Paxil) and sertraline (Zoloft). Fluoxetine is frequently used to treat major depression, obsessive compulsive disorder, bulimia nervosa, panic disorder, body dysmorphic disorder, premenstrual dysphoric disorder, and trichotillomania.
Abstract
Fluoxetine is an oral drug that is used for treating depression. It is in a class of drugs called selective serotonin reuptake inhibitors (SSRIs), a class that also contains citalopram (Celexa), paroxetine (Paxil) and sertraline (Zoloft).
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Brand Names
Prozac
Sarafem
Fontex
Manufacturers
TEVA USA
IVAX PHARMA
MYLAN
MALLINCKRODT PHARMA
LIBERTY PHARMA
SANDOZ
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History
Fluoxetine was discovered by the Eli Lilly and Company in 1970. In February 1977, Dista Products Company, a division of Eli Lilly & Company, presented a new drug request to the U.S. Food and Drug Administration (FDA) for fluoxetine. Fluoxetine appeared on the Belgian market in 1986. After over a decade, the FDA gave its final approval in December 1987, and a month later Eli Lilly began marketing Prozac; annual sales in the U.S. reached $350 million within a year.
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Uses
Fluoxetine is frequently used to treat major depression, obsessive compulsive disorder, bulimia nervosa, panic disorder, body dysmorphic disorder, premenstrual dysphoric disorder, and trichotillomania. Caution should be taken when using any SSRI for bipolar disorder as this can increase the likelihood of mania; however, fluoxetine can be used with an antipsychotic for bipolar.It has also been used for cataplexy, obesity, and alcohol dependence, as well as binge eating disorder.
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Pharmacology
Like several other SSRIs fluoxetine is metabolized by CYP2D6.
CYP2D6 is involved in the metabolism of approximately 20% of drugs in clinical use, and displays large individual-to-individual variability in activity due to genetic polymorphisms
More than 80 CYP2D6 variant alleles have been identified; however, 4 of the most prevalent alleles, CYP2D6*3, *4, *5, and *6, account for 93-97% of CYP2D6 poor metabolizers (PMs)
CYP2D6*4, the most common variant (~25% frequency in whites), causes a splicing defect. CYP2D6*3 (2.7% frequency) causes a frameshift mutation, and CYP3D6*5 (2.6%) is an entire deletion of the CYP2D6 gene; individuals homozygous for these alleles have no CYP2D6 activity
The impact of CYP2D6 activity is further complicated in some SSRIs (eg, fluoxetine, fluvoxamine, paroxetine, sertraline) that in addition to being substrates for CYP2D6, are also known to at moderately inhibit CYP2D6 activity
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Schedule
It is not a controlled substance in the US.
Dosage
The dosage depends on the reason why it is prescribed for an individual. In general,
Initial: 20 mg PO qDay
May consider gradually increasing dose after several weeks by 20 mg/day; not to exceed 80 mg qDay.
For children about 8 years: initial 10-20 mg PO qDay
May gradually increase dose after 1 week; not to exceed 20 mg qDay
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Drug Interactions
This drug has been found to mildly interact with:
astemizole
cisapride
furazolidone
isocarboxazid
lumefantrine
moclobemide
pargyline
phenelzine
pimozide
procarbazine
terfenadine
thioridazine
tranylcypromine
Among the more serious interactions are:
amiodarone
amitriptyline
buspirone
carvedilol
disopyramide
dosulepin
hydromorphone
ibutilide
iloperidone
milnacipran
morphine
nebivolol
oxymorphone
paroxetine
pentamidine
sertraline
sibutramine
And a selected few with significant contradincation interactions would be with:
abiraterone
aceclofenac
acemetacin
aspirin
bosentan
bromfenac
bupropion
ziprasidone
zolmitriptan
zotepine
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Adverse Effects
Headache (20-25%)
Nausea (20-25%)
Insomnia (15-20%)
Anorexia (10-15%)
Anxiety (10-15%)
Asthenia (10-15%)
Diarrhea (10-15%)
Nervousness (10-15%)
Somnolence (10-15%)
Dizziness (5-10%)
Dry mouth (5-10%)
Dyspepsia (5-10%)
Sweating (5-10%)
Tremor (5-10%)
Decreased libido (2-5%)
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Contraindications
Hypersensitivity
Concomitant MAOIs: risk of serotonin syndrome
Concomitant pimozide or thioridazine
Breastfeeding
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Cautions
Clinical worsening and suicidal ideation may occur despite medication in adolescents and young adults (18-24 years old)
Risk of serotonin syndrome when used with other strong serotonergic drugs
Risk of bleeding, GI and other, when used in combo with NSAIDs, aspirin or drugs affecting coagulation
Activation of mania/hypomania (screen for bipolar disorder); hyponatremia; seizures
Mydriasis reported, caution in patients with acute narrow-angle glaucoma
Hypoglycemia reported, may alter glycemic control in patients with diabetes
Pregnancy: Conflicting evidence regarding use of SSRIs during pregnancy and increased risk of persistent pulmonary hypertension of the newborn.
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Pricing
The pricing varies depending on what form one would like to buy and the brand.
The 10mg capsule is priced in between $0.37 to $19.49. The prices for 20mg/5 ml solution vary from $0.33 to $1.46. The 20mg tablet would cost $0.99 while the 5mg tablet is priced in between $0.06 to $10.30. The price range for the 40mg tablet is from $0.97 to $41.14
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Referenecs
[1] http://reference.medscape.com/drug/prozac-sarafem-fluoxetine-342955#90
[2] http://www.medicinenet.com/fluoxetine/article.htm
[3] http://www.sciencedirect.com/science/article/pii/002432059500209O
[4] http://www.drugs.com/monograph/fluoxetine-hydrochloride.html
[5] http://reference.medscape.com/drug/prozac-sarafem-fluoxetine-342955#10
[6] http://reference.medscape.com/drug/prozac-sarafem-fluoxetine-342955#3
[7] http://reference.medscape.com/drug/prozac-sarafem-fluoxetine-342955#4
[8] http://reference.medscape.com/drug/prozac-sarafem-fluoxetine-342955#5
