Warnings


What are the risks of taking Proscar (finasteride)?


Proscar can cause serious health problems in certain groups of people. Talk to your doctor or pharmacist about other treatment options if you are at high risk of the following complications.

  • Birth Defects: Proscar can be harmful to an unborn baby if a pregnant woman or a woman who may become pregnant handles broken or crushed tablets of this medicine. If you are currently pregnant, think you could be pregnant, or are planning a pregnancy, and have come in contact with broken or crushed finasteride tablets, wash the area with soap and water immediately and call your doctor.

  • PSA Levels: Prostate-specific antigen (PSA) is a blood test for prostate cancer. Proscar can lower PSA levels, which can affect the results of prostate cancer screening tests. Your doctor will check your PSA level 6 months after starting treatment with Proscar to establish a new baseline. They will then keep an eye on your PSA levels periodically after that.

  • Prostate Cancer: Taking Proscar can increase the risk of developing high-grade prostate cancer. The risk is higher in men over the age of 55. Talk to your doctor about other treatment options for BPH if this is a concern for you.

  • Blood Donation: Men on Proscar cannot donate blood until at least 1 month after the last dose. Finasteride in donated blood can be harmful to unborn babies if the blood is given to pregnant women.

Your healthcare provider or pharmacist can discuss other treatment options for BPH if you are at risk of complications from Proscar (finasteride) use.


What should I tell my doctor before starting Proscar (finasteride)?

Tell your doctor if you have previously had an allergic reaction to finasteride, any of the ingredients in Proscar tablets, or any other medications. Your pharmacy can provide you with a list of ingredients.

Tell your health care professional about all your medical conditions. Proscar may not be suitable for people with certain medical conditions. Make sure your doctor knows about any history of liver disease, prostate cancer, or severe problems with urination. 

Give your healthcare provider a complete list of your current medications, including prescription drugs, over-the-counter medications, dietary supplements, vitamins, and herbal products. This can help avoid serious drug interactions.

What precautions should I take while on Proscar (finasteride)?

Keep all your healthcare appointments while taking Proscar. Your doctor may order blood tests to check liver function and/or PSA levels. They may also want to keep an eye on adverse effects while you’re on this medicine. Before having any laboratory test, tell the doctor and laboratory personnel that you are on finasteride.

Call your doctor immediately or go to the emergency room if you experience symptoms such as rash, hives, itching, swelling of the face or lips, or difficulty breathing or swallowing. These can be signs of an allergic reaction and require immediate medical attention.

Finasteride can cause changes in breast tissue. Tell your doctor if you experience any tenderness, pain, lumps, or enlargement of the breasts while on this medicine.

Proscar can lead to a decrease in the amount of semen ejaculated during sex. It does not, however, affect sperm count and will not affect your ability to have children.

Remember that Proscar is only for use by adult men. Women, especially those who are pregnant or may become pregnant, should not touch broken or crushed tablets as this can be harmful to the unborn baby.

What drugs can interact with Proscar (finasteride)?

Taking Proscar with certain other medications can affect how it works. Drug interactions between finasteride and other medicines, such as St. John’s Wort, can increase the risk of serious adverse effects. Your doctor may prescribe a different BPH treatment, change the dose of your medicines, and/or monitor you carefully for side effects if there are known interactions between Proscar and your other medications. 

To avoid Proscar drug interactions, be sure to give your doctor and pharmacist a list of all your current medications, including prescription medicines, over-the-counter medications, dietary supplements, vitamins, and herbal products. 

Also, tell your healthcare provider if you smoke, drink alcohol, or use recreational drugs because some of these substances can cause serious health complications when used with prescription drugs.