Finasteride is a synthetically produced drug designed to treat benign prostatic hyperplasia and hair loss in men. Finasteride is an inhibitor of the second type of 5α-reductase. 5α-reductase is an enzyme that is responsible for the transformation of testosterone into dihydrotestosterone. This is a synthetic 4-azasteroid compound that perfectly reduces the level of dihydrotestosterone in the blood.
From the history
In Africa, a tribe was discovered in which adolescents were found to receive masculine symptoms immediately after adolescence. It became interesting to doctors and scientists from the US, when investigating this phenomenon, they found another interesting fact – in the adult mule gender of the tribe, no enlarged prostate was found. As a result, they concluded that men do not genetically have an enzyme that converts testosterone to dihydrotestosterone, which affects the growth of prostate tissue. Further came to the conclusion that if you remove this enzyme, it will not work. In order to block this element, invented finasteride, which is widely known as proscar. Proscar helps the opposite development of the prostate gland. People who have fallen ill without surgery, urination improves, difficulties disappear in the beginning of urination and the feeling of unfinished emptying of the bladder disappears.
The 5-alpha reductase inhibitor is an enzyme that converts testosterone into a more mobile dihydrotestosterone. Reduces the amount of dihydrotestosterone in the blood and tissues of the prostate gland. Infringes the stimulation of dihydrotestosterone on the growth of benign prostatic hyperplasia (BPH).
Finasteride has an effect on reducing the size of the gland, improving the flow of urine and reducing symptoms associated with benign prostatic hypertrophy. To reduce the clinical manifestations of the disease may need a couple months of treatment.
Basic properties of finasteride
For medical purposes Finasteride is prescribed for the treatment of benign BPH. The dosage recommended by the FDA is equal to five milligrams, once a day. To achieve a therapeutic result, it may take about six months to use finasteride. When the finasteride is closed, the disease may reappear after seven months. Finasteride affects the decline in symptoms associated with benign prostatic hyperplasia.
Finasteride has a positive effect only during its application. Hair, grown at its reception, can again drop out in six-twelve months after refusal of therapy.
Finasteride has antiandrogenic properties, it is not enough when used in hormone replacement therapy in transsexuals.
At the moment there is a small amount of data on the reception of Finasteride for this purpose and the arguments of its effectiveness in this area are insufficient. Scientists have proved that Finasteride softens the result of withdrawal after a long intake of alcohol.
Synthetic 4-azasteroid compound, competitive inhibitor of steroid 5-alpha-reductase type II. This intracellular enzyme converts testosterone into active 5-alpha-dihydrotestosterone (DHT). Inhibition of DHT production leads to a decrease in the size of the prostate gland. Finasteride does not have an affinity for the androgen receptor, so that testosterone-dependent symptoms do not appear during its use in the form of weight gain and hirsutism. As a result of the use of finasteride, the concentration of DHT in the serum, urine and DHT present in the prostate is reduced, thereby reducing the size of the prostate, increasing the maximum volume flow rate of urine, reducing the risk of acute urinary retention and the risk of need for surgery. Reducing the concentration of DHT in the scalp prevents miniaturization of the hair follicles, stopping the process of baldness. After oral administration, the bioavailability is about 80%, the intake of food does not affect the absorption. Finasteride approximately 93% binds to plasma proteins, penetrates the blood-brain barrier. Metabolism occurs in the liver under the influence of the cytochrome P-450 isoenzyme CYP3A4. About 60% of the drug is excreted from the body with feces, about 40% – with urine. t1 / 2 is 5-6 hours, in patients over the age of 70 years – 8 hours. The effect of the action, which is to decrease the concentration of DHT, is kept for 24 hours.
Finasteride, indications for use
Finasteride is indicated for benign prostatic hyperplasia (to reduce the size of the prostate gland, to increase the maximum rate of urine outflow and to reduce symptoms associated with hyperplasia, to reduce the risk of acute urinary retention and the associated likelihood of surgical intervention.
Hypersensitivity to finasteride and other components of the drug, prostate cancer, obstruction of the urinary tract, children’s age.
With caution – a violation of the liver.
Dosing and Administration
Finasteride is taken orally regardless of food intake, 1 tablet (5 mg) per day for 6-7 months.
Side effects of Finasteride
The undesirable effects of the drug are due to a decrease in testosterone levels in the male body. In view of this, the decrease in libido, impotence, and enlargement of the mammary glands develop.
The most common side effects:
- infertility in men;
- decreased libido;
- allergic reactions in the form of angioedema, Quincke’s edema;
- disruption of the liver (increased liver enzymes – ALT, AST);
- coarsening and soreness of mammary glands.