Dutasteride – dual inhibitor of 5-a redukgazy. It inhibits the activity of 5 a -reductase isozymes type 1 and 2, which are responsible for the conversion of testosterone 5 a-dihydrotestosterone (DHT). DHT androgen is the main responsible for the hyperplasia of the glandular prostate tissue.
Influence on concentrations of DHT and testosterone. Dutasteride maximum effect on reducing the concentration of DHT is dose-dependent and observed after 1 to 2 weeks after the start of treatment. After 1 and
1 week. dutasteride receiving a dose of 0.5 mg per day, median serum concentrations of dihydrotestosterone is reduced by 85 and 90%.
Dosing and Administration
Dutasteride can be used as monotherapy and in combination with a z blocker tamsulosin.
Dutasteride can be taken regardless of the meal.
The effect is quite fast, but the treatment should be continued for at least 6 months in order to objectively evaluate the effect of the drug.
Adult males (including the elderly)
Recommended dosage is one capsule dutasteride (0.5 mg) once a day orally. The capsules should be swallowed whole, do not chew, do not open, because the contents of the capsule may cause irritation of the oropharynx.
Patients with impaired renal function
When receiving 0.5 mg of dutasteride daily urine allocated less than 0.1% of the dose, so dose adjustment for patients with impaired renal function is not required.
Patients with impaired liver function
Dutasteride is subjected to intensive metabolism, and its half-life of 3-5 weeks and therefore caution should be exercised in treating patients with dutasteride with impaired hepatic function.
Approximately 19% of the 2167 patients who applied dutasteride during the two-year placebo-controlled clinical trial phase III, have developed adverse reactions during the first year of treatment. Most adverse reactions were mild to moderate, and the reproductive system.
It was not in the course of further two-year open-label extension study of changes in the profile of adverse reactions identified.
The table below shows adverse reactions from controlled clinical studies and post-marketing surveillance: The following adverse reactions, which, in the investigator’s opinion, associated with drug intake (frequency of not less than 1%) during the first year of treatment were more frequent in patients of the group receiving dutasteride than in the group receiving placebo. Adverse events in the post-marketing studies reported in spontaneous reports, so the actual frequency of the reactions is not known.
The drug can be administered independently from the meal. Capsules should be swallowed whole, not chewed and do not open because the contents of the capsule may cause irritation of the mucosa of the oropharynx.
Benign prostatic hyperplasia (BPH)
In adult males (including the elderly) The recommended dose of the drug Avodart is 1 capsule. (500 mg), 1 time / day.
Although an improvement on the background of the drug comes pretty quickly, treatment should be continued for at least 6 months in order to objectively evaluate the therapeutic effect.
For the treatment of BPH Avodart drug may be designated as a monotherapy or in combination with an alpha 1 adrenoblokatorami.
When receiving the 500 mg / day is released through the kidneys than 0.1% of the dose, so there is no need to reduce the dosage in patients with impaired renal function.