Flutamide is an oral anti-androgen medication that blocks the effects of testosterone in the body.
Flutamide belongs to a class of medicines called non-steroidal anti-androgens. Its main job is to block the effects of male hormones, known as androgens, in the body. By doing so, it helps control conditions that grow in response to these hormones. Flutamide is the active ingredient found in the product Eulexin.
In Hong Kong, the most common brand that contains flutamide is Eulexin. It is supplied as oral tablets, typically in 250 mg strength. Both the branded version and the generic name “flutamide” are authorised under the Pharmacy and Poisons Ordinance and can be dispensed by registered pharmacies. The tablet form is the usual presentation, although some markets offer the ingredient in combination tablets with other cancer medicines. Availability may vary between private hospitals and community pharmacies, but the product is listed in the Hong Kong Drug Formulary.
These uses are based on the drug’s ability to block androgen receptors, reducing the hormone-driven stimulation of tumour cells or hair follicles.
Flutamide travels through the bloodstream to cells that have androgen receptors. Once there, it fits into the receptor like a key that blocks the lock, preventing natural male hormones from attaching. Without the hormone signal, cells that depend on androgens receive a “stop” signal, which can slow or halt their growth. The blocking effect begins within a few days after the first dose, but the full clinical response may take several weeks.
People taking flutamide often notice mild, short-lived reactions such as:
These symptoms usually improve with time or simple supportive care.
Although rare, some reactions need urgent attention:
If any of these signs appear, seek emergency care without delay.
Flutamide may interact with:
Because each medication containing flutamide may have its own interaction profile, always refer to the specific product information for a complete list.
Store flutamide tablets in a cool, dry place away from direct sunlight and moisture. Keep them out of reach of children. Treatment length varies; some patients use it for a few months, while others may continue for years under specialist supervision. Remember that each brand or combination product may have different instructions, so always read the label that comes with your specific medication.
Androgen: A male hormone that influences growth of certain tissues, including prostate cells.
Anti-androgen: A substance that blocks the action of androgens on their receptors.
Receptor: A tiny structure on a cell that receives signals from hormones or drugs.
This article offers general educational information about flutamide as an active substance used in various medicines. Its purpose is to help patients better understand the ingredient and the conditions it is used to treat. It is not a substitute for professional medical advice or for the specific instructions provided with individual products. Medicines containing flutamide may differ in formulation, strength, and directions for use. Always consult the labeling of your particular medication and follow your healthcare provider’s guidance for complete information on proper use, dosage, and safety.
