Author: Charles Frank

Finasteride: MedlinePlus Drug Information

what is the drug finasteride

Women who are pregnant or may get pregnant must not handle broken or crushed finasteride tablets. If a pregnant woman comes into contact with broken or crushed tablets she should check with her care team. Exposure to whole tablets is not expected to cause harm as long as they are not swallowed. Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

It may take at least 6 months before your symptoms improve. Do not donate blood while you are taking this medication. This will prevent giving this medication to a pregnant female through a blood transfusion. Ask your care team when it is safe to donate blood after you stop taking this medication.

The results of MTOPS are consistent with the findings of the 4-year, placebo-controlled study a long-term efficacy and safety study [see Clinical Studies (14.1)] in that treatment with finasteride reduces the risk of acute urinary retention and the need for BPH-related surgery. In MTOPS, the risk of developing acute urinary retention was reduced by 67% in patients treated with finasteride compared to patients treated with placebo (0.8% for finasteride and 2.4% for placebo). Also, the risk of requiring BPH-related invasive therapy was reduced by 64% in patients treated with finasteride compared to patients treated with placebo (2% for finasteride and 5.4% for placebo). In the clinical study using 1 mg tablets, the bioavailability of finasteride is observed at approximately 65% and is not affected by food. Finasteride is approximately 90% protein bound with a volume of distribution of 76 L at a steady-state and can cross the blood-brain barrier.

what is the drug finasteride

Do not start, stop, or change the dosage of any medicines without your doctor’s approval. Of the total number of subjects included in a long-term efficacy and safety study, 1480 and 105 subjects were 65 and over and 75 and over, respectively. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients. No dosage adjustment is necessary in the elderly [see Clinical Pharmacology (12.3) and Clinical Studies (14)]. Finasteride tablets administered in combination with the alpha-blocker doxazosin are indicated to reduce the risk of symptomatic progression of BPH (a confirmed ≥4 point increase in American Urological Association (AUA) symptom score).

1 Effects on Prostate Specific Antigen (PSA) and the Use of PSA in Prostate Cancer Detection

The condition that finasteride is used to treat depends on the type of the drug used. Finasteride oral tablet is available as the brand-name drugs Proscar and Propecia. Generic drugs usually cost less than the brand-name version. In some cases, they may not be available in every strength or form as the brand-name drug.

  1. If these effects are mild, they may disappear within a few days or a couple of weeks.
  2. The effect of finasteride will only last as long as the medicine is taken.
  3. Finasteride is a medication that treats the symptoms of an enlarged prostate and a condition called benign prostatic hyperplasia.
  4. Do not share finasteride with another person, even if they have the same symptoms you have.
  5. Make sure lab personnel and all your doctors know you use this drug.
  6. Your doctor will write the number of refills authorized on your prescription.

Talk to your doctor about the benefits and risks.Women and children should not use this medication. Single doses up to 400 mg and multiple doses up to 80 mg per day for three months are well-tolerated and did not result in any significant adverse reactions in the clinical studies. Until further experience is obtained, no specific treatment for an overdose with finasteride can be recommended. There are no reports of overdoses of finasteride, resulting in clinically significant toxicity. However, overdoses could occur as an extension of previously reported adverse drug effects, including orthostatic hypotension.

If you take too much, you’re at a higher risk for developing negative reactions. These can include decreased sex drive, trouble getting or keeping an erection, ejaculation disorder, increase in breast size or tenderness, and rash. Lab and/or medical tests (such as prostate exams, PSA levels) should be done while you are taking this medication. Follow your doctor’s instructions for examining your breasts and testicles, and report any lumps right away.

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Read the Patient Information Leaflet if available from your pharmacist before you start taking finasteride and each time you get a refill. If you have any questions, ask your doctor or pharmacist. Ask your pharmacist any questions you have about refilling your prescription. This medication may be prescribed for other uses; ask your doctor or pharmacist for more information. Hypersensitivity to any components of this product (4).Females who are or may potentially be pregnant (4, 5.3, 8.1, 16). This list may not describe all possible side effects.

what is the drug finasteride

Talk to your care team about the use of this medication in children. This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions. The easiest way to lookup drug information, identify pills, check interactions and set up your own personal medication records. Your doctor will perform tests to make sure finasteride is the right treatment for you. This is not a complete list of side effects and others may occur. There are other drugs available to treat your condition.

It is proposed that the type I 5α-reductase and type II 5α-reductase is responsible for the production of one-third and two-thirds of circulating DHT, respectively. Finasteride is used to shrink an enlarged prostate (benign prostatic hyperplasia or BPH) in adult men. This medication works by decreasing the amount of a natural body hormone (DHT) that causes growth of the prostate.Finasteride is not approved for prevention of prostate cancer. It may slightly increase the risk of developing a very serious form of prostate cancer.


To help prevent interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. Finasteride works by decreasing the amount of the hormone dihydrotestosterone (DHT) in your body.

It is usually taken once a day with or without food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Do not take more or less of it or take it more often than prescribed by your doctor. There have been postmarketing reports of male infertility and/or poor seminal quality; normalization or improvement of seminal quality has been reported after discontinuation of finasteride [see Adverse Reactions (6.2)].

Finasteride tablets are not approved for the prevention of prostate cancer. The American Society of Clinical Oncology (ASCO) and American Urological Association (AUA) released a joint statement in 2008. They developed a clinical practice guideline to assist physicians and patients with making informed decisions after reviewing the risks and benefits of the medication. You may need blood work while you are taking this medication. For example, your care team may have you take a blood test called PSA for the screening of prostate cancer. Make sure your care team knows you are taking this medication before you take a PSA test.

Call your doctor if you have any unusual problems while taking this medication. Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient.