Finasteride

This information from Lexicomp^® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Propecia; Proscar

Brand Names: Canada

ACH-Finasteride; AG-Finasteride; APO-Finasteride; Auro-Finasteride; BIO-Finasteride; DOM-Finasteride [DSC]; JAMP-Finasteride; M-Finasteride; MINT-Finasteride; PMS-Finasteride; Propecia; Proscar; RAN-Finasteride [DSC]; RIVA-Finasteride; SANDOZ Finasteride; SANDOZ Finasteride A; TEVA-Finasteride

What is this drug used for?

• It is used to help hair growth in male pattern baldness. It may take 3 months to see the full effect.
• It is used to treat the signs of an enlarged prostate. It may take a few months to see the full effect.
• It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take this drug?

• If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you are able to get pregnant or breast-feed. This drug is not approved for use in these patients. If you are pregnant, plan on getting pregnant, or are breast-feeding, talk with your doctor.

This drug may interact with other drugs or health problems.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

For all uses of this drug:

• Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
• To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
• This drug may affect certain lab tests. Tell all of your health care providers and lab workers that you take this drug.
• A very bad form of prostate cancer was seen more often in some men taking drugs like this one than in those who were not. This was seen in a trial of men taking these drugs to lower the chance of prostate cancer. Talk with your doctor.
• Rarely, male breast cancer has happened with this drug. Talk with your doctor.
• This drug may affect sperm. This may affect being able to father a child. Talk with the doctor.
• Pregnant people must not handle crushed or broken tablets. If a pregnant person touches a crushed or broken tablet, wash the area with soap and water right away.

For enlarged prostate:

• Have a rectal exam (to check prostate gland) and blood work (PSA test). Talk with your doctor.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• A lump in the breast, breast pain or soreness, or nipple discharge.
• Enlarged breasts.
• Very bad dizziness or passing out.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Feeling tired or weak.
• This drug may cause lowered interest in sex, ejaculation problems, or trouble getting or keeping an erection. This could go on after you stop this drug. Talk with your doctor if these effects go on or bother you.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Take with or without food.
• Take this drug at the same time of day.
• Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.

What do I do if I miss a dose?

• Skip the missed dose and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.

How do I store and/or throw out this drug?

• Store tablets in the original container at room temperature. Keep the cap tightly closed.
• Protect from light.
• Store in a dry place. Do not store in a bathroom.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else’s drugs.
• Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2023-12-11

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