Generic Name: finasteride (fih NAH steh ride)
Brand Names: Propecia, Proscar
What is finasteride?
Finasteride prevents the conversion of testosterone to dihydrotestosterone (DHT) in the body. DHT is involved in the development of benign prostatic hyperplasia (BPH).
Finasteride (Propecia) is used for the treatment of male pattern hair loss. Finasteride (Proscar) is used to treat symptoms of benign prostatic hyperplasia (BPH) in men with an enlarged prostate.
Finasteride may also be used for purposes not listed in this medication guide.
What is the most important information I should know about finasteride?
Finasteride 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. Although finasteride is not for use by women, this medication 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 this medication from a broken or crushed tablet, wash the area with soap and water right away. Before taking finasteride, tell your doctor if you have ever had an allergic reaction to this medication, or to a similar medicine called dutasteride (Avodart).
Using finasteride may increase your risk of developing prostate cancer. Your doctor will perform tests to make sure you do not have other conditions that would prevent you from safely using finasteride.
Call your doctor at once if you notice any breast lumps, pain, nipple discharge, or other breast changes. These may be signs of male breast cancer.
What should I discuss with my healthcare provider before taking finasteride?
Finasteride 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.
To make sure you can safely take finasteride, tell your doctor if you have any of these other conditions:
liver disease, or abnormal liver enzyme tests;
prostate cancer;
a bladder muscle disorder;
stricture of your urethra;
if you are unable to urinate; or
if you have ever had an allergic reaction to a similar medicine called dutasteride (Avodart).
Using finasteride may increase your risk of developing prostate cancer. Your doctor will perform tests to make sure you do not have other conditions that would prevent you from safely using finasteride. Although finasteride is not for use by women, this medication 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 this medication from a broken or crushed tablet, wash the area with soap and water right away.
How should I take finasteride?
Take this medication exactly as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended. Follow the directions on your prescription label.
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.
To be sure this medication is helping your condition and not causing harmful effects, your blood may need to be tested often. Your doctor will also test your prostate specific antigen (PSA) to check for prostate cancer. Visit your doctor regularly.
Use finasteride regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.
Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.
See also: Finasteride dosage (in more detail)
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 any of these 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 breast lumps, pain, nipple discharge, or other breast changes. These may be signs of male breast cancer.
Less serious side effects may include:
impotence, loss of interest in sex, or trouble having an orgasm;
abnormal ejaculation;
swelling in your hands or feet;
swelling or tenderness in your breasts;
dizziness, weakness;
feeling like you might pass out;
headache;
runny nose; or
skin rash.
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.
Finasteride Dosing Information
Usual Adult Dose for Benign Prostatic Hyperplasia:
5 mg orally once a day.
Patients should be evaluated for efficacy after 6 to 12 months. If after this time there is no improvement, finasteride should be discontinued. Doses greater than 5 mg/day do not result in increased dihydrotestosterone suppression and should not be used.
Several long-term studies (up to ten years) have concluded that finasteride leads to durable improvement in urinary tract symptoms, flow rate, and prostate volume.
Usual Adult Dose for Androgenetic Alopecia:
For the treatment of male pattern hair loss (androgenetic alopecia) in men only . (Safety and efficacy have been demonstrated in men between 18 to 41 years of age with mild to moderate hair loss of the vertex and anterior mid scalp area.):
Recommended Dosage: 1 mg once a day.
In general, daily use for three months or more is necessary before benefit is observed. Continued use is recommended to sustain benefit. Withdrawal of treatment leads to reversal of effect within 12 months.
What other drugs will affect finasteride?
There may be other drugs that can interact with finasteride. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.
More finasteride resources
- Finasteride Side Effects (in more detail)
- Finasteride Dosage
- Finasteride Use in Pregnancy & Breastfeeding
- Drug Images
- Finasteride Drug Interactions
- Finasteride Support Group
- 11 Reviews for Finasteride - Add your own review/rating
- finasteride Advanced Consumer (Micromedex) - Includes Dosage Information
- Finasteride Prescribing Information (FDA)
- Finasteride Professional Patient Advice (Wolters Kluwer)
- Finasteride Monograph (AHFS DI)
- Finasteride MedFacts Consumer Leaflet (Wolters Kluwer)
- Propecia Prescribing Information (FDA)
- Propecia MedFacts Consumer Leaflet (Wolters Kluwer)
- Propecia Consumer Overview
- Proscar Prescribing Information (FDA)
- Proscar Consumer Overview
Compare finasteride with other medications
- Androgenetic Alopecia
- Benign Prostatic Hyperplasia
Where can I get more information?
- Your pharmacist can provide more information about finasteride.
See also: finasteride side effects (in more detail)
