Finasteride Safety Information

What Is This Medication?

Finasteride is an oral medication used to treat male pattern hair loss (androgenetic alopecia) in men. It works by blocking the enzyme 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT). DHT is the primary hormone responsible for shrinking hair follicles in men with genetic hair loss. By reducing DHT levels, finasteride slows hair loss and can promote regrowth of hair in affected areas, particularly at the crown and mid-scalp. Finasteride for hair loss is prescribed at a 1 mg daily dose and typically requires three to six months of consistent use before visible results appear.

Who Should Consider This Treatment?

Finasteride may be appropriate for adult men who are experiencing early to moderate male pattern hair loss and want to slow progression or regrow hair. It is most effective when started early in the hair loss process. Your healthcare provider will evaluate your pattern of hair loss, medical history, and overall health to determine if finasteride is a suitable option for you. Finasteride is intended for use by men only.

Who Should Not Use This Medication?

Do not use finasteride if you:

• Are a woman or a child. Finasteride is approved only for use in adult men. Women should not take finasteride, particularly women who are or may become pregnant.
• Are pregnant or may become pregnant (women): Finasteride can be absorbed through the skin and may cause serious birth defects in a developing male fetus. Women who are pregnant or may become pregnant should not handle crushed or broken finasteride tablets.
• Have a known hypersensitivity or allergy to finasteride or any of its components

Warnings and Precautions

• PSA Test Effects: Finasteride lowers prostate-specific antigen (PSA) levels by approximately 50%. If you undergo PSA screening for prostate cancer, inform your doctor that you take finasteride so results can be interpreted correctly.
• Some men have reported sexual side effects that continued after stopping finasteride. While this is rare, discuss any concerns about sexual function with your provider.
• If you notice breast lumps, pain, nipple discharge, or other breast changes, contact your healthcare provider promptly.
• Report any changes in mood, including new or worsening depression, anxiety, or suicidal thoughts, to your provider immediately.
• If you stop taking finasteride, any hair that was regrown or maintained by the medication will typically be lost within 12 months of discontinuation.
• Men taking finasteride should not donate blood until at least one month after their last dose, to prevent administration of finasteride to a pregnant transfusion recipient.

Common Side Effects

The most commonly reported side effects include:

• Decreased libido (reduced sexual desire)
• Erectile dysfunction (difficulty achieving or maintaining erections)
• Decreased ejaculate volume
• Breast tenderness

These side effects occur in a small percentage of men and are often mild. In most cases, they resolve after discontinuing the medication or may improve over time with continued use. Clinical studies have shown that these effects occur in roughly 2 to 4 percent of men taking finasteride 1 mg daily.

Serious Side Effects

While rare, the following serious side effects have been reported. Contact your healthcare provider or seek medical attention if you experience:

• Depression: New or worsening depressive symptoms, including persistent sadness, loss of interest, or changes in sleep or appetite
• Breast enlargement or tenderness(gynecomastia): Swelling, lumps, pain, or nipple discharge from the breast
• Testicular pain: Persistent or unusual pain in the testicles
• Persistent sexual side effects (post-finasteride syndrome): In rare cases, sexual side effects including decreased libido, erectile dysfunction, and ejaculation disorders have been reported to persist after discontinuation of finasteride
• Allergic reactions: Rash, itching, hives, swelling of the lips, tongue, throat, or face

Drug Interactions

Finasteride has limited known drug interactions. However, it is important to tell your healthcare provider about all medications you are taking, including prescription drugs, over-the-counter medicines, vitamins, and herbal supplements. Your provider will review your complete medication list to identify any potential interactions or concerns. If you are also taking dutasteride or other 5-alpha reductase inhibitors, inform your provider, as combining these medications is not recommended.

Before Starting Treatment

Before taking finasteride, inform your healthcare provider if you:

• Have liver disease or abnormal liver function tests
• Have prostate cancer or are being screened for prostate cancer
• Have urinary problems or difficulty urinating
• Have a history of depression or mood disorders
• Have a history of breast cancer or breast conditions
• Have a female partner who is pregnant or planning to become pregnant (discuss precautions for handling the medication)
• Plan to have a PSA test in the near future

How to Use This Medication

Finasteride is taken by mouth as a 1 mg tablet once daily, with or without food. Take it at approximately the same time each day for the best results. Consistency is key with finasteride, as it needs to be taken daily to maintain its effect on DHT levels. You may not notice visible improvement for three to six months, and some men may require up to 12 months of treatment before the full benefit is apparent. If you miss a dose, skip it and take your next dose at the regular time. Do not take a double dose. Do not crush or break the tablets, as the active ingredient can be absorbed through the skin. Store at room temperature, away from moisture and heat. Keep out of reach of women and children.