Flutamide: Uses, Mechanism of Action, Administration, Side Effects and Precautions

It is approved for the treatment of stage D2 prostate cancer, where the cancer has spread from its place of origin to different sites in the body.

Generic name: Flutamide.

Trading name: Eulexin.

It is important for patients to remember that physicians have the ability to prescribe drugs for conditions other than those for which the drug has been approved by the FDA.

Patients who have received a prescription for this drug for a condition other than the one it is approved for may wish to discuss this problem with their physician.

What is the mechanism of action?

Flutamide belongs to a group of medicines called antiandrogens. The prostate cancer is stimulated to grow by male hormone, testosterone.

Anti-androgens inhibit the effects of testosterone on cancer cells, thus eliminating the growth stimulus.

Flutamide is often given in combination with another hormonal agent, classified as a leuteinizing hormone-releasing hormone (LHRH) agonist, which helps to block the body’s production of testosterone.

How is flutamide usually given?

Flutamide is a capsule that is taken by mouth and the dose depends on several factors, including the condition being treated, the size of the patient, the particular regimen being used, and the general health of the patient.

Flutamide dosage should be evenly spaced throughout the day if patients take more than one dose per day. The capsules can be opened and mixed with soft food, but not liquid. Patients and their physicians will discuss the optimal schedule for flutamide.

How are patients supervised?

Patients often have scheduled meetings with their healthcare provider while they are being treated with flutamide.

Usually, blood will be drawn to monitor the functions of some organ systems, especially the liver. Patients may also undergo physical examinations, scans, or other measures to assess side effects and response to therapy.

Patients should notify their physician if they notice:

  • Yellow skin or eyes.
  • Loss of appetite
  • Sickness.
  • Vomiting
  • Rash.
  • General feeling of tiredness.
  • Abdominal pain.
  • Flu symptoms.

These symptoms may indicate liver damage.

What are the common side effects of flutamide treatment?

Side effects occur in 30% or more of patients:

  • Swelling or tenderness in the breasts.
  • Bochornos.
  • Reduced sex drive
  • Erectile dysfunction.
  • Nipple discharge

What are the less common side effects (occur in 10% to 29% of patients) of flutamide treatment?

  • Abnormalities in liver function levels, as determined by blood tests.
  • Nausea and vomiting
  • Diarrhea.
  • Changes in appetite
  • Discoloration of urine (greenish yellow).

This is not a complete list of side effects. Some patients may experience other side effects that are not listed here.

Patients may wish to discuss the other less common side effects of this drug with their doctor, some of which can be serious.

Some side effects may require medical attention. Other side effects do not require medical attention and may go away during treatment.

Patients should check with their doctor about side effects that continue or are bothersome.

What can patients do to help relieve or prevent discomfort and side effects?
  • Pay particular attention to your doctor’s instructions and inform your doctor of any side effects.
  • Maintain adequate rest and nutrition.
  • Wear sunscreen and protective clothing and try to minimize sun exposure.
  • Drink plenty of fluids (patients should ask their doctor about how much fluid to drink in a day).
  • Eat small meals often to help relieve nausea.
  • Patients experiencing hot flashes may wish to wear light clothing, stay in a cool environment, and place cold washcloths on their body or head to alleviate their symptoms.

Are there any special precautions that patients should be aware of before starting treatment?

  • Patients should inform their physician if they are pregnant, nursing, or planning a family in the near future. This medicine may cause birth defects. It is important to use some form of contraception while undergoing treatment.
  • It is important that patients inform their doctor of any pre-existing conditions (chickenpox, heart disease, kidney disease, liver disease, lung disease, etc.) as they can be made worse by this drug.
  •  Patients should inform their physician if they have glucose-6-phosphate dehydrogenase (G6PD) deficiency, blood disorders, or are smokers as patients with these conditions may be at increased risk of toxicity.
  • Patients should inform their physician of any other medications they are taking (either prescription or non-prescription, including vitamins, herbs, etc.) as they may interfere with treatment.
  • Patients should inform their physician if they are taking warfarin as they may require additional monitoring and dosage adjustment to decrease the risk of bleeding.
  • Patients should check with their doctor before starting any new drug or nutritional supplement.
  • Patients should inform their physician of any known drug or food allergies or any drug reactions they have experienced in the past.
  • If you miss an oral dose, do not double the doses. Patients should contact their doctor in this case.
  • Keep the tablets out of the reach of children and return to the pharmacy for safe disposal if treatment ends.

When should patients notify their physician?

  • Chest pain or fast heartbeat.
  • Difficulty breathing.
  • Yellowing of the eyes or skin.
  • Loss of appetite
  • Sickness.
  • Vomiting
  • Acne.
  • General fatigue
  • Abdominal pain.
  • Flu-like symptoms.
  • Persistent or severe nausea or vomiting.
  • Diarrhea.
  • Pain, numbness, or tingling in the arms or legs.
  • Swelling of the arms or legs, or weight gain.
  • Depression or nervousness

Important limitations of use

The information provided above about the medication you have selected is provided for information only and is not a substitute for consulting an appropriate physician.

Patients should discuss the suitability of a particular drug or chemotherapy regimen with their physician.

As with any printed reference, the use of certain medications, regimens, and drug dosages may become outdated over time, as new information may have been published and generally accepted after the last update of this printed information.

Please note that healthcare professionals are fully responsible for practicing to current standards, avoiding the use of outdated regimens, employing good clinical judgment when selecting medications and / or regimens, when calculating doses for individual patients.