Medically reviewed: April 24, 2017
What is finasteride?
This medicine is for use in men only.
Finasteride may also be used for purposes not listed in this medication guide.
Finasteride should never be taken by a woman or a child.
Finasteride can cause birth defects if a woman is exposed to it during pregnancy. Finasteride tablets should not be handled by a woman who is pregnant or may become pregnant.
Before taking this medicine
You should not use finasteride if you are allergic to it.
This medicine should never be taken by a woman or a child. Finasteride can be absorbed through the skin, and women or children should not be permitted to handle finasteride tablets.
Using finasteride may increase your risk of developing prostate cancer. Talk with your doctor if you have concerns about this risk.
To make sure finasteride is safe for you, tell your doctor if you have:
liver disease, or abnormal liver enzyme tests;
a bladder muscle disorder;
stricture of your urethra;
if you are unable to urinate; or
Although finasteride is not for use by women, this medicine can cause birth defects if a woman is exposed to it during pregnancy. Finasteride tablets should not be handled by a woman who is pregnant or who may become pregnant.
If a woman accidentally comes into contact with a broken or crushed tablet, wash the area with soap and water right away.
How should I take finasteride?
Your doctor will perform blood tests to make sure you do not have conditions that would prevent you from safely using finasteride.
Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.
Take this medicine with a full glass of water.
Finasteride can be taken with or without food. Take the medicine at the same time each day.
Use finasteride regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.
It may take up to 3 months or longer before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.
While using finasteride, you may need frequent blood tests. Your doctor will also test your prostate specific antigen (PSA) to check for prostate cancer.
Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid while taking finasteride?
Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.
Finasteride side effects
Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you notice any signs of male breast cancer, such as:
Common side effects may include:
loss of interest in sex;
trouble having an orgasm; or
The sexual side effects of finasteride may continue after you stop taking this medicine. Talk to your doctor if you have concerns about these side effects.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
What other drugs will affect finasteride?
Other drugs may interact with finasteride, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Copyright 1996-2018 Cerner Multum, Inc. Version: 8.01.
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