Overview
11 DESCRIPTION Dutasteride and tamsulosin hydrochloride capsules contain dutasteride (a selective inhibitor of both the type 1 and type 2 isoforms of steroid 5 alpha-reductase, an intracellular enzyme that converts testosterone to DHT and tamsulosin (an antagonist of alpha 1A -adrenoceptors in the prostate).
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Dutasteride and tamsulosin hydrochloride capsules are a combination of 2 drugs with different mechanisms of action to improve symptoms in patients with BPH: dutasteride, a 5-alpha-reductase inhibitor, and tamsulosin, an antagonist of alpha 1A -adrenoreceptors. Dutasteride Dutasteride inhibits the conversion of testosterone to DHT. DHT is the androgen primarily responsible for the initial development and subsequent enlargement of the prostate gland. Testosterone is converted to DHT by the enzyme 5-alpha-reductase, which exists as 2 isoforms, type 1 and type 2. The type 2 isoenzyme is primarily active in the reproductive tissues, while the type 1 isoenzyme is also responsible for testosterone conversion in the skin and liver.
Indications
- 1 INDICATIONS AND USAGE Dutasteride and tamsulosin hydrochloride capsules are a combination of dutasteride, a 5-alpha-reductase inhibitor, and tamsulosin, an alpha-adrenergic antagonist, indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate. ( 1.1 ) Limitations of Use: Dutasteride-containing products, including dutasteride and tamsulosin hydrochloride capsules, are not approved for the prevention of prostate cancer. ( 1.2 ) 1.
Common Doses
- 0.5 mg
- 0.4 mg
Dosage
2 DOSAGE AND ADMINISTRATION The recommended dosage of dutasteride and tamsulosin hydrochloride capsules is 1 capsule (0.5 mg dutasteride and 0.4 mg tamsulosin hydrochloride) taken once daily approximately 30 minutes after the same meal each day. The capsules should be swallowed whole and not chewed or opened. Contact with the contents of the dutasteride and tamsulosin hydrochloride capsule may result in irritation of the oropharyngeal mucosa. Take one capsule daily approximately 30 minutes after the same meal each day. ( 2 ) Swallow capsule whole. ( 2 )
Contraindications
- 4 CONTRAINDICATIONS Dutasteride and tamsulosin hydrochloride capsules are contraindicated for use in: Pregnancy. Dutasteride use is contraindicated in females who are pregnant. In animal reproduction and developmental toxicity studies, dutasteride inhibited development of male fetus external genitalia. Therefore, dutasteride and tamsulosin hydrochloride capsules may cause fetal harm when administered to a pregnant female. [see Warnings and Precautions ( 5.6 ), Use in Specific Populations ( 8.1 ) ] . Patients with previously demonstrated, clinically significant hypersensitivity (e.g.
Side Effects
- 6 ADVERSE REACTIONS The most common adverse reactions, reported in ≥1% of subjects treated with coadministered dutasteride and tamsulosin are ejaculation disorders, impotence, decreased libido, dizziness, and breast disorders. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AvKARE at 1-855-361-3993 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience The clinical efficacy and safety of coadministered dutasteride and tamsulosin, which are individual components of dutasteride and tamsulosin hydrochloride capsules, have been evaluated in a multicenter,...
Interactions
- 7 DRUG INTERACTIONS There have been no drug interaction trials using dutasteride and tamsulosin hydrochloride capsules. The following sections reflect information available for the individual components. 7.1 Cytochrome P450 Inhibition Dutasteride Dutasteride is extensively metabolized in humans by the CYP3A4 and CYP3A5 isoenzymes. The effect of potent CYP3A4 inhibitors on dutasteride has not been studied. Because of the potential for drug-drug interactions, use caution when prescribing a dutasteride-containing product, including dutasteride and tamsulosin hydrochloride capsules, to patients...