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 previous therapy or ineffective hormone therapy.

Pharmacological effect

Pharmacodynamics

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

Does not have estrogenic, antiestrogenic, progestogenic or antigestagenic activity.

Pharmacokinetics

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

Plasma protein binding is 94-96%. After repeated oral administration at a dose of 250 mg 3 times a day, the equilibrium concentration of flutamide and its active metabolite in the blood plasma was achieved after the 4th dose.

Metabolized to form the active metabolite hydroxyflutamide and 5 other metabolites.

Excreted mainly in the urine, 4.2% of the dose is excreted in feces within 72 hours. T1/2 of hydroxyflutamide is 6 hours.

In elderly patients, T1/2 is 8 hours after a single dose and 9.6 hours at steady state concentration.

Special instructions

When treating prostate cancer, it is necessary to monitor liver function (laboratory tests should be performed once a month for the first four months and then regularly). If liver enzyme levels increase 2-3 times the upper limit of normal values ​​and/or jaundice occurs in the absence of liver metastases, flutamide should be discontinued. When the first symptoms of liver dysfunction appear, such as itching, dark urine, nausea, vomiting, persistent loss of appetite, yellowing of the skin or whites of the eyes, pain in the right hypochondrium, or flu-like symptoms of unknown origin, you should immediately consult a doctor.

When assessing the results of differential diagnosis of male hypogonadism, it is necessary to focus on the following indicators: in healthy people with normal basal excretion of gonadotropins after administration of the drug, an increase in their secretion by 1.5 times or more is observed; with primary hypogonadism, the initial excretion of gonadotropins is significantly increased, less often – normal, the use of the drug leads to a further increase in their secretion by 1.5-2 times or more; with secondary hypogonadism, the initial excretion of gonadotropins is reduced, less often – normal, a significant increase in their excretion after taking the drug is not observed.

Active ingredient

Flutamide

Composition

1 tablet contains:

Active ingredients:

flutamide 250 mg.

There are 20 tablets in a polyethylene bottle.

In a cardboard package there is 1 polyethylene bottle.

Contraindications

Hypersensitivity to flutamide or acetanilide.

Side Effects

From the endocrine system: gynecomastia and/or galactorrhea.

From the digestive system: nausea, vomiting, jaundice, diarrhea, increased activity of liver transaminases.

From the side of water-electrolyte metabolism: fluid retention.

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

Interaction

It is believed that drug interactions are possible with the simultaneous use of flutamide with paracetamol, opioid analgesics, and NSAIDs.

Storage conditions

In a dry place, protected from light, at a temperature of 15–30 °C

Shelf life

3 years

Manufacturer

New Farm Inc., Canada