Finasteride FAQ

Finasteride, also known as Propecia, is a pill taken once per day that prevents the conversion of testosterone to dihydrotestosterone (DHT) in the body to reduce hair loss due to androgenetic alopecia. The following are some of the most frequently asked questions we receive about finasteride:

General Questions

Finasteride Sexual Side effectsHow does finasteride work?
Finasteride belongs to a group of medications known as 5 alpha-reductase inhibitors. These medications have an anti-androgenetic effect which means that this enzyme inhibitor will block the conversion of testosterone to the more potent form of testosterone known as dihydrotestosterone (DHT). Daily administration of finasteride helps reduce miniaturization of the hair on the scalp of men experiencing male pattern baldness. It has been shown to be most effective for crown balding but it will help in any location on the scalp where the hair follicle still exists. Therefore, once the follicle has permanently ceased to exist on the scalp, no amount of finasteride will reverse the loss and result in hair growth.

How can I get the product?
Finasteride is available by prescription only after your physician examines and diagnoses you with male pattern baldness. It is available in 1 milligram tablets for hair loss and 5 milligram tablets for prostate enlargement. Some patients purchase the five milligram finasteride, or Proscar, and take one quarter tablet every day for its affordability. The prescription can be obtained by visiting a hair loss specialist, a dermatologist or a general practitioner.

Can finasteride be used as topical product on the scalp?
Oral finasteride is the most effective FDA approved medication for hair loss  DHT blockers including finasteride have been tried topically for years. However, there is little scientific evidence that indicates its effectiveness if applied topically.

Is there an age limit?
There is no age limitation associated with the use of finasteride in adult men as long as the patient has normal liver function.  Finasteride is metabolized by the liver through the cytochrome P450 pathway. If you are older, and on multiple mediations, it is important to check with your doctor to make sure your other medications are compatible in order to help minimize possible side effects.

When is the best time to start finasteride?
The decision to start finasteride is one you make together with your hair restoration physician. In the US, finasteride is available by prescription only. Therefore, once you are diagnosed with androgenetic alopecia, you should start it soon to help you keep the hair you have. Finasteride is not recommended for individuals under the age of 18 due to its interaction with sexual development.

How long do I have to wait before it works?
Once you start using finasteride, it takes about 3 months before you begin to see any effects. The final results can be seen 6-12 months after you start using the medication. The expectation is to see a reduction in hair loss rather than a growth of new hair. Patients with significant hair miniaturization or thinning may notice an increase in their hair volume due to an increase in the size of the miniaturized hair.

What if I forget to take it?
If you forget to take the pill one day, there is no need to double the dosage. Taking more than one pill per day will not increase the results seen from the use of finasteride but you may experience more side effects.

Can I double the effect of finasteride by taking it with Minoxidil?
Both medications are FDA approved for hair loss. However, the ways they function in the body are different. There are studies that look at the efficacy of finasteride in comparison to minoxidil versus the two together. We know finasteride is more potent for male patterned hair loss than minoxidil. While studies show an improved result when minoxidil is added to finasteride, you will not see a doubling of the effect and the added benefit will be minimal.

If side effects occur with finasteride using the regular dosage of 1mg a day, can I take it every other day or at a lower dose and still have it be effective?
The recommended daily dose of finasteride is 1mg a day. A daily dosage less than this may not be as effective.

Is there any difference between finasteride and Propecia?
There should be no difference between generic finasteride and the brand name Propecia as finasteride is the generic name for Propecia. Technically, the formulas are the same and one should not experience any difference between the products (except in your wallet).

What are the differences between finasteride and minoxidil?
There are several differences between finasteride (Propecia) and minoxidil (Rogaine) including:

  1. Finasteride is only available via prescription while minoxidil can be purchased over the counter.
  2. Finasteride should only be used by male patients suffering from male patterned baldness while minoxidil can be used by both men and women
  3. Finasteride is taken in a pill form once per day and minoxidil is applied topically to the scalp twice per day
  4. A common side effect of finasteride is decreased libido while side effects of minoxidil are usually limited to skin irritation and itching in the area being treated

Finasteride Side Effects

What are the most common side effects of Propecia?
The most commonly reported side effect of finasteride is decreased sex drive/libido. The other side effects that are not as common, but are concerning to patients, are breast enlargement/breast tenderness and testicular pain.

Is the sexual side effect of Propecia reversible?
Permanent sexual side effects of finasteride have been reported only in small scale retrospective studies. These reports have not been reproduced through large-scale prospective studies. Most of these reports did not take into account advancing age and other underlying issues. In general, the sexual side effects should lessen and eventually dissipate after use of the medication is discontinued.

Are there any alternatives if I experience side effects?
Finasteride and Rogaine are the only two FDA approved medications for the treatment of androgenetic alopecia. Alternatives to finasteride may be helpful as they are chemically similar but users may experience greater side effects. Products such as Avodart and Aldactone fall into this category. Other over the counter medications such as saw palmetto and pumpkin seed oil show reported evidence for hair loss prevention. Vitamins such as Iron, Zinc and Biotin are only effective in reducing hair loss if you are clinically deficient in them. For more detailed information regarding alternative treatments to finasteride, see our web page: Medical Hair Loss Treatment.

What should I do if I have side effects from finasteride?
If you experience any intolerable finasteride related side effects, stop taking the medication immediately. If the side effects do not abate after you stop taking finasteride, contact your physician and inquire about alternative treatments to aid with your hair loss.

Are there any allergies that prevent me from taking finasteride?
Allery to finasteride is very rare. However, you should not take finasteride if you are allergic to it or to any other ingredients in the product.

Should I use finasteride after a hair transplant?
Transplanted hair removed from the permanent zone of the scalp is not susceptible to the effects of DHT which means the longevity of these hairs is maintained. This implies that patients will not need to use finasteride to maintain the results of the transplanted hair. However, your native hair outside the permanent zone can continue to thin over time since they remain susceptible to the effects of DHT. The hair prone to hair loss is where finasteride is of benefit either before and/or after a hair transplant.

Patients who have significant miniaturization of scalp hair may experience shock loss after hair transplant. We emphasize finasteride use for the first six months after hair transplant to minimize shock loss.

Can finasteride affect fertility in men?
There have not been any significant reports of infertility with the use of finasteride in humans.

Can it cause depression?
There are reports of mood changes after taking finasteride. If you experience mood changes or depression while taking finasteride, you need to stop the medication and discuss this with your doctor.

Women and Finasteride

Can women use finasteride?
Finasteride is only prescribed for men. Pregnant women should not use the medication as it can affect the normal development of the genitals in a male fetus. Finasteride may be absorbed through the skin so doctors recommend that women not handle broken or crushed finasteride tablets.

My husband is using finasteride, should he stop using it if I plan on becoming pregnant?
Finasteride is secreted in all bodily fluids and is also present in semen. Fortunately, the amount of finasteride that may be absorbed in your body is negligible. Scientific studies do not recommend the stopping of finasteride use by male partners during pregnancy.