Flutamide, tablets 250 mg, 20 pcs.

Pharmacodynamics

An antiandrogenic agent of non-steroidal structure. By blocking androgen receptors of target cells it prevents development of biological effects of endogenous androgens, which leads to disruption of replication of tumor cells. Helps to reduce the size and density of the prostate gland, prevents the development of the metastatic process.

Does not have estrogenic, anti-estrogenic, gestagenic and anti-gestagenic activity.

Pharmacokinetics

After oral administration is quickly and completely absorbed from the gastrointestinal tract.

The binding to plasma proteins is 94-96%. After multiple oral doses of 250 mg 3 times/day, the equilibrium plasma concentration of flutamide and its active metabolite was reached after the 4th dose.

It is metabolized to form the active metabolite hydroxyflutamide and 5 other metabolites.

It is excreted mainly in the urine, 4.2% of the dose is excreted in the feces within 72 hours. T_1/2 hydroxyflutamide is 6 hours.

In elderly patients, T_1/2 is 8 h after a single administration and 9.6 h at equilibrium concentration.

Indications

Palliative treatment of prostate cancer with metastases in the absence of prior therapy or ineffective hormone therapy.

Active ingredient

Composition

1 tablet contains:

Active ingredients:

Flutamide 250 mg.

In a polyethylene vial, 20 tablets.

There is 1 polyethylene vial in the carton.

How to take, the dosage

Ingestion: 250 mg 3 times a day. Frequency and duration of use depend on the treatment regimen.

Interaction

It is believed that there may be a drug interaction when flutamide is used simultaneously with paracetamol, opioid analgesics, NSAIDs.

Special Instructions

In treatment of prostate cancer, liver function should be monitored (laboratory tests should be performed once a month for the first four months and regularly thereafter). In case the level of liver enzymes is 2-3 times higher than the upper limit of normal values and/or in case of jaundice in the absence of liver metastases, flutamide should be discontinued. If the first symptoms of liver dysfunction occur, such as itching of the skin, darkened urine, nausea, vomiting, persistent loss of appetite, yellowing of the skin or whites of the eyes, pain in the right subcostal area or flu-like symptoms of unclear origin should be immediately consulted with a physician.

When evaluating the differential diagnosis of male hypogonadism, the following indicators should be considered: in healthy individuals with normal basal gonadotropin excretion after administration of the drug there is an increase in their excretion by 1.5 times or more; in primary hypogonadism the initial gonadotropin excretion is significantly increased, less often normal, the drug administration leads to a further increase in their excretion by 1.5-2 times or more; in secondary hypogonadism the initial gonadotropin excretion is reduced, less often normal, no significant increase in their excretion after the drug administration is observed.

Contraindications

Hypersensitivity to flutamide or acetanilide.

Side effects

Endocrine system disorders: gynecomastia and/or galactorrhea.

Digestive system disorders: nausea, vomiting, jaundice, diarrhea, increased liver transaminase activity.

Water-electrolyte metabolism: fluid retention.

Other: rarely – headache, thromboembolism, renal dysfunction, sleep disorders, subcutaneous hemorrhage, lupus-like syndrome.