Finasteride

What is the FDA-approved use of finasteride?

Finasteride is FDA-approved for treating androgenic alopecia (male pattern hair loss) in men.

Mechanism of Action

Finasteride acts as a specific inhibitor of Type II 5α-reductase, an enzyme that converts testosterone to DHT. It predominantly targets the Type II isozyme, found in tissues like the prostate, seminal vesicles, and hair follicles. By inhibiting this enzyme, finasteride significantly reduces DHT concentrations in both serum and tissues. In men with male pattern hair loss, it decreases DHT levels in the scalp, affecting miniaturized hair follicles and potentially interrupting the progression of androgenetic alopecia.

Who should not use finasteride?

Do not use finasteride if there is a personal or family history of hypersensitivity to finasteride or any of its components. For women, especially those who are pregnant or planning pregnancy, avoiding contact with broken or crushed finasteride tablets is crucial to prevent potential harm to the fetus. Finasteride use can result in abnormalities in the male fetus's external genitalia. You must be over 18 to use finasteride.

What should I tell a provider before starting finasteride?

Ensure you disclose your entire medical history to your healthcare provider. Be aware that withholding or providing inaccurate health and medical history to obtain treatment can have serious consequences, potentially including death.

Comorbidities:

Personal or family history of hypersensitivity to finasteride.

Pregnancy and special populations:

Pregnancy: May cause fetal harm. Discontinue finasteride when pregnancy is recognized.
Males of Reproductive Potential: Finasteride has been found to cause sexual dysfunction that continued after discontinuation of treatment, including erectile dysfunction, libido disorders, ejaculation disorders, and orgasm disorders; male infertility and/or poor seminal, and testicular pain
have any other medical conditions, including problems with your prostate or liver

Drug-interactions:

While no drug interactions of clinical importance have been identified, finasteride may impact the absorption of concomitantly administered oral medications. Use with caution.

How should I use finasteride?

Topical finasteride should be applied to the affected areas of the scalp as directed by your provider. The topical formulation is meant for external use only and should not be ingested or applied to other body parts. Wash your hands thoroughly after application.
Oral finasteride can be taken with or without meals. You should take oral finasteride exactly as prescribed and should not change your dosing regimen without discussing it with your provider first.

What side effects should I be aware of with finasteride?

Common side effects associated with finasteride, though typically mild, may include:

Decreased sexual desire.
Ejaculation problems.
Testicular pain.
Depression.

Serious side effects linked to finasteride use require attention, especially during treatment initiation or dosage adjustments. Seek immediate medical attention if experiencing severe symptoms or a medical emergency.

Watch out for these potential serious side effects of finasteride:

Changes in Breast Tissue: Any changes in breasts such as lumps, pain, or nipple discharge.
Depression: Persistent feelings of depression.
Allergic Reactions: Rash, itching, hives, swelling of the lips and face, difficulty breathing, or swallowing.
Sexual Function: Difficulty getting or maintaining an erection, a decrease in semen volume, or problems with ejaculation.
Testicular Pain: Unusual or severe testicular pain.
Erectile Dysfunction: Difficulty achieving an erection that continues after discontinuing the medication.
Male Breast Cancer: In rare cases, the development of male breast cancer.

It is important to talk to your healthcare provider about any potential risks and benefits of taking finasteride, and to report any side effects or concerns promptly.

The above does not encompass all potential side effects, medication interactions, or studies related to finasteride. Unreported or yet undiscovered side effects might exist.

Research Links