Q: What do I do if I start experiencing side effects on finasteride? — L.L. ~ Riverdale, N.Y.
A: Don’t panic, just stop the medication and let your doctor know. He or she will give you guidance based on your symptoms.
Posted by Updated 2018-07-03
Recent news reports, coupled with warnings from Merck and the FDA, about Propecia’s possible persistent sexual side effects have caused growing concern about this popular hair loss treatment. An increasing number of men now fear that Propecia (finasteride 1mg) will cause permanent sexual dysfunction.
A 2014 meta-analysis, however, found that the number of self-reported cases of persistent sexual dysfunction by patients given finasteride was statistically no different from the number reported by patients given a placebo.
This latest research supports the conclusion of existing literature that there is no correlation between finasteride use and persistent or permanent sexual dysfunction. That said, this is an important issue that still needs to be studied.
Posted by Updated 2015-10-09Q: I’ve heard that FDA added a description of reports of male infertility to the side effect labels of both Propecia and Proscar (finasteride). Is this a likely side effect in your experience? — S.S., Rolling Hills, California
A: Propecia (finasteride 1mg) may, uncommonly, lead to male infertility by changing the consistency of the male ejaculate as well as decreasing the sperm count.
Ejaculate is a combination of sperm produced by the testes and a viscous fluid made by the prostate. Since finasteride shrinks the prostate it make the ejaculate less viscous (more watery).
Most patients taking Propecia and trying to conceive have no issues.
If one is trying to conceive for 4-6 months and having difficulty, then it is reasonable to stop taking Propecia.
It is important to know that taking Propecia while trying to conceive will not lead to congenital deformities or issues with the fetus as long as the women does not come in direct contact with the medication.
Posted by Updated 2018-07-03Q: As a Propecia user, I was alarmed when I read headlines last year about about a new study indicating very high rates of depression and erectile dysfunction caused by Propecia, with symptoms persisting even after the drug was stopped. However, when I read the articles, this “study” appeared to be survey of 61 men who had taken Propecia and already reported sexual problems who were then asked about symptoms of depression. These rates of depression were compared to a small survey of men who had hair loss but had never taken Propecia.
Anyone with a basic understanding of statistics would know such a survey was deeply flawed. First, it is a textbook example of a bad data sample — to get sound results you have to start with an unbiased and random group of people who took the drug, not a self-selected group of men already suffering symptoms. The study also confuses correlation with causation — because these men are suffering from ED or depression does not necessarily mean it was caused by the drug. Am I missing something here, or did the media just report these “findings” with no scrutiny on what was actually studied? — Jonathan, Brooklyn, NY
A: Jonathan, I think you’re right on the mark. The way the study was conducted raises a lot of concern about the accuracy of the findings. It is really important that additional data is obtained in a controlled way, as this will be most useful for physicians in advising patients. I addressed concern on these reports on the Hair Transplant Blog last year. The issue of persistent sexual dysfunction as a side-effect of finasteride is an on-going issue that we take very seriously. I sit on the International Society of Hair Restoration Surgery (ISHRS) Task Force on Finasteride Adverse Events, so this is an issue that we watch very closely.
Read more about Propecia and Persistent Side Effects
Read more about Propecia (finasteride)
Posted by Updated 2020-02-17Q: Dr. Bernstein, I am an attending at Mass General Hospital in Boston and would like to ask you regarding your experiences using finasteride for male androgenetic alopecia. While I have not noticed any side effects in the patients that I have been treating, I increasingly get questions regarding side effects based on the recent media attention to reports of potentially permanent problems regarding libido or erectile dysfunction. I know that in the literature there is a slight increase of reversible sexual dysfunction (~4% vs. ~2% in placebo) with Propecia, and no convincing evidence to date in the medical literature that have used controlled studies regarding permanent problems even after discontinuing Propecia. — S.Z., Boston, Massachusetts
A: That is correct.
Q: I know that you have treated many patients over a long period of time, and I was thus wondering what your take is on potentially permanent sexual dysfunction after taking finasteride. Have you seen any convincing reports/patients or do you have any concerns regarding irreversible side effects?
A: I have seen 5 cases in over 10,000 patients on finasteride that complained of this but, of course, there is no way to know for sure if there is a cause and effect relationship. As you know, real side effects may be followed by psychological ones and if the sexual dysfunction has another cause, then stopping finasteride would have no effect on the symptoms. The incidence of sexual dysfunction in the population of men on finasteride is about 30%, so one would expect these numbers to be much higher just due to the normal incidence. It is really a difficult situation to understand. The experience that my colleagues and I have in our practices is much different than one would expect after reading the numerous anecdotal reports on the internet.
Q: Would you think it is safe to say that any potential sexual dysfunction is reversible after discontinuing the use of finasteride?
A: I don’t think that anyone knows at this point. The FDA is coming down on the side of caution and saying that it is possible, although it is not based on any new studies. If the phenomenon is real, the possible mechanism is not yet known.
Q: In the relatively few patients that I have treated with Propecia, they did not even report temporary problems regarding libido or erectile dysfunction. Do you think they are real or rather attributed to Propecia simply because the patient is made aware of these potential side effects?
A: I think that psychological effects may account for many cases. At this time, it is still not clear if a physiologic “post-finasteride syndrome” is real. A lot more work needs to be done before we have a definitive answer to this question.
Posted by Updated 2017-12-11The central finding of a 2004 study led by Italian researcher Dr. Antonella Tosti, in which he and his team investigated sexual dysfunction in hair loss patients being treated for androgenetic alopecia, was that there was no statistically significant change in sexual function after four to six months of treatment with finasteride 1mg (Propecia).
Interestingly, the research team found that sexual side effects were actually less common than reported in the clinical trials of the drug.
Posted by Updated 2013-07-08Q: You prescribed Propecia for my hair loss. I was wondering if the new news report on Propecia side effects has altered your opinion regarding the safety of this drug? — N.D., Belle Meade, Tennessee
A: It has not changed. I believe you are referring to Dr. Michael Irwig’s study at George Washington University published in the Journal of Sexual Medicine. I was already aware of the study when I prescribed the medication for you and we discussed the risk of persistent side effects at your consult.
Although all types of data should be considered, it is important to realize that this was not a scientific study, but a survey. It had very significant selection bias. From this type of study, one can’t prove cause and effect relationships or even get a sense of actual incidences. These were patients who were recruited because they already had persistent sexual dysfunction. Since it is not clear if their persistent problems were directly due to the medication or from other factors, and since these patients were selected, rather than randomly assigned, the additional information can be gained from the report is very limited.
That said, the reporting of persistent side effects should not be taken lightly, but should be viewed in the context of all available data. It is extremely important for us to continue to be vigilant, as this is a very significant issue, but it is equally important not to make decisions on data sensationalized in the media. As a result of the finasteride data, some are presenting surgery as a more reasonable alternative than medication. For a young person, that is usually not the case.
Posted by Updated 2017-12-11On April 11, 2012, the U.S. Food and Drug Administration (FDA) announced changes to the professional labels for Propecia (finasteride 1 mg) and Proscar (finasteride 5 mg) to expand the list of sexual adverse events reported to FDA as some of these events have been reported to continue after the drug is no longer being used (note that erectile dysfunction after stopping use of these drugs was added as a known event in 2011). The new label changes include:
Q: I am 27 years old and I have been on Propecia for 12 months now. Honestly, I have seen no response from it. In my dermatologist’s opinion I am a non-responder. I asked about Avodart and he said, since Propecia didn’t help then Avodart won’t help as well since both are DHT blockers, and if one didn’t work the other won’t either. In your opinion do you think Avodart is better? I have read that it blocks more DHT than Propecia. What is the dosing for Avodart? If someone does not respond to Propecia will they also not respond to Avodart? — A.C., West University Place, Texas
A: Avodart (dutasteride) is more effective than Propecia (finasteride) and some patients will respond to dutasteride who do not respond to finasteride. Dutasteride decreases serum DHT about 90% compared to 70% for finasteride. The usual starting dose of Avodart is 0.5mg a day. That said, it is not FDA approved for use in hair loss and if a person has sexual side effects, the side effects are more likely to be persistent after stopping the medication compared to finasteride.
Posted by Updated 2017-12-11In response to anecdotal evidence of sexual side effects continuing after stopping Propecia (finasteride 1mg), the International Society of Hair Restoration Surgery (ISHRS) has published a press release for the hair restoration community about the safety and efficacy of the drug. The release notes that scientific data gathered from extensive testing finds no correlation between persistent sexual dysfunction and Propecia.
Posted by Updated 2015-09-25Q: I heard that the sexual side effects of Propecia are irreversible. Is this true? — L.R., Parsippany, NJ
A: The sexual side effects of finasteride (Propecia) begin to subside soon after the medication is discontinued. This would make sense since the drug finasteride is a reversible inhibitor of DHT. Although it is possible for side effects to be persistent after stopping the medication, this situation seems to be very uncommon and a cause and effect relationship is still in question.
Posted by Updated 2017-12-11Q: I started using both Propecia (finasteride) and Rogaine for roughly the past 15 weeks. In the last month I’ve been experiencing pain in my left testicle area. At first I thought this may be due to Varicocele; however, after some quick internet searches I thought it may also be the Propecia. The pain doesn’t seem to be in the testicle itself as much as the surrounding veins on the left side. What should I do? — B.L., Houston, TX
A: Your symptoms are the classic ones of a varicocele, namely pain on the left side that is adjacent to the testicle. Symptoms of finasteride would more likely be bilateral, although the discomfort does not need to be in the testicle itself. If your symptoms are worse at the end of the day when you have been standing, and less in the AM when you first arise, these suggest a varicocele.
In your pain is consistently worse towards the end of the day, I would see a urologist, as surgical intervention might be warranted, particularly if it is affecting sperm counts – which should be checked as part of the evaluation.
If this is not the case, then stop finasteride for a least a month and see if the symptoms subside. If they do go away off finasteride, I would not take the medication again. If the symptoms persist off finasteride, I would still see a urologist.
Posted by Updated 2015-04-23Q: I’ve now been taking finasteride for just over 5 months. I have noticed that my semen quality has changed just in the last 3 months, and it seems now much less in quantity and is quite watery and clear in color. I think the current problems are due to the finasteride, what do you think? — S.F., Rolling Hills, California
A: Finasteride, the active drug in Propecia, can change the quality of the semen, since it is decreasing the component of seminal fluid that is secreted by the prostate. You may want to consider having your sperm counts checked, as finasteride can lower this. If the symptoms are not bothering you, and your sperm counts are normal, it should be OK to continue the medication. If you were having difficulty conceiving, then I would stop the medication.
Posted by Updated 2017-12-11Q: I heard that there is a new drug on the market called Avodart for prostate enlargement which might help with hair loss as it blocks the conversion of testosterone to DHT better than Finasteride and is more effective than Propecia. Do you recommend taking it and if so what is the dose? — Y.B., Orlando, Florida
A: I am currently not recommending that patients take Dutasteride for hair loss, although it is more effective than Propecia, finasteride 1mg. (Dutasteride 0.5, the dose generally used for hair loss, seems to be slightly more effective than finasteride 5m in reversing miniaturization.)
The reasons that I am hesitant to prescribe it at present are outlined in the Hair Restoration Answers question, “Is Avodart Safe?“
Posted by Updated 2017-12-11Q: My friend is taking Avodart, he bought it over the internet. Is it safe to take? — T.G., Denver, Colorado
A: Avodart (dutasteride 0.5mg) was approved by the FDA for the treatment of prostate enlargement in men in 2002. Avodart has not been approved for the treatment of androgenetic hair loss, although physicians can use an approved medication in ways other than for which it was specifically approved. That said, the use of dutasteride certainly requires a doctor’s supervision.
Posted by Updated 2017-12-11
