A man has decided to start on finasteride – say, in January. By March, he is in the bathroom assessing his progress under the unforgiving glare of the bulb, twisting his head this way and that, and deciding that, overall, nothing has changed.
He is likely correct – in the short term, a mere three months, little is likely to have changed. He may also have failed to consider the subtleties and nuances of the benefits. While he is unlikely to be seeing new growth in his shower, he may well have less on his desk at the end of the day.
Finasteride is not a magic bullet, a rapid cure, or an instant fix. Its benefits are primarily preventative with a secondary bonus of rebuilding – to a limited extent – the density of existing hair. It rarely presents dramatic before-and-after photos; the usual results are more subtle.
What does finasteride actually do?
Dihydrotestosterone or DHT is a hormone to which some men are particularly sensitive. In these men, it can cause the follicles on the scalp to shrink over time. First, a robust and healthy follicle produces slightly thinner hair, then, after several cycles, even less, until eventually it is little more than a patch of downy fluff.
Finasteride inhibits the enzyme responsible for converting testosterone to DHT. In particular, a daily 1 mg dose reduces scalp DHT levels by approximately 80%. This is enough for the follicles sensitive to DHT to resume their normal function.
However, it is important to note that it only inhibits the conversion of testosterone to DHT and does not lower overall testosterone levels. It also does not magically cause new follicles to appear; if a man has had a particular spot on his head completely bald for years, medication is unlikely to restore it.
How effective is it?
The evidence is largely positive. Large-scale randomized controlled trials with over a thousand men each have shown that, compared to a placebo, finasteride is significantly more effective at maintaining and improving hair density. The men who took the medication either retained more hair or grew it back on average compared to those who took the inactive substance. This was also demonstrated photographically – the finasteride group generally appeared to have better results.
The most important consideration, however, is that the results are meaningful. While the finasteride group may not have seen dramatic improvements, for some men, an improvement is a large amount of hair on the crown or the ability to continue having a full head of hair five years later if they had not already lost a significant amount.
The crown and the top of the head respond well to finasteride, but the temples rarely show signs of regrowth, especially in men with severe recession. The front is gradually improved, but rarely restored at a mature hairline. The medication is unlikely to do much for the widow’s peak, unless it is not a mature hairline.
When will results appear?
One of the most disheartening traits of finasteride is that it requires a seemingly unbending commitment to long-term use. Some men will see few or no visible results for the first six months – for the first few months, the best results are often seen in the mirror. Fewer hairs are shed, but this is subjective, and it is not uncommon for men to continue to lose hair at the same rate for the first year.
By the fourth to sixth month, some men may see a lessening of shedding or a slight change in the shape of their hair, especially when viewed from the top or when styling. However, these changes are often minimal and largely imperceptible.
The most significant changes are typically seen between six and twelve months. If the medication is to have a noticeable thickening effect, it will usually begin to show around this time. This, in many ways, is the key point in the treatment – a year later, the dermatologist will be able to assess whether there is enough improvement to warrant further medication.
Our timeline for results on finasteride goes into greater detail on the subject.
It is useful to take regular photos every three months to track progress. It is best to use dry hair when doing this to eliminate excess frizziness, and it is a good idea to take them in the same lighting and at the same angle. Selfies with a phone are often not helpful, as a particularly good or bad haircut can fool the eye.
Taking a photo at the same time every year can be an effective way to track progression – or the lack thereof.
What happens if I stop?
The medication only blocks the production of DHT while it is in the system. As such, once it is stopped, DHT levels return to their previous norm, and hair loss accelerates. The hair which had been retained or regrown is gradually lost over the next year – on average, it takes roughly that long for the medication to wash out completely.
Missing one dose will not have a noticeable effect – simply take one the next day. It is unwise to take an extra dose.
It is this long-term nature that makes the side effects of the medication so relevant – if the medication is being used for a substantial period of time, then the risks become more pertinent.
Does it cause sexual dysfunction?
It can, but it is not common. In the original year-long trials for Propecia, 1.8% of men who took finasteride reported reduced libido, compared to 1.3% who took the placebo. 1.3% of the finasteride group and 0.7% of the placebo group reported erectile dysfunction, and 1.2% versus 0.7% for ejaculatory dysfunction, respectively.
Pooling all the sexual dysfunction together, the numbers were 3.8% for the finasteride group and 2.1% for the placebo.
What this means is that while there may be some association between the medication and sexual dysfunction, it is not strongly supported. There is a measurable but small effect, potentially exacerbated by expectations, but it is not definitive. Men who take the medication are slightly more likely to report some sexual dysfunction, but it is not a guaranteed result.
In addition, those same trials show that in men who stopped the medication, the symptoms ceased – and for many, they did not recur. There is also evidence, anecdotal and otherwise, that the medication can cause sexual dysfunction long after it has been discontinued. Overall, the risk is very difficult to quantify, but it is a definite possibility that should not be dismissed outright.
If a man begins to notice any change in his sexual function after beginning the medication, it is probably best to consult the prescribing doctor rather than attempting to rationalize it away. Our article on Propecia side effects and impotence goes into much greater detail on the subject.
Does it cause depression?
It can – or rather, it can contribute to the development of depression, which in turn can lead to other issues. However, these are also relatively rare. The medications have been on the market for a considerable time, and several regulatory agencies have taken note of this potential risk. Notably, European authorities have confirmed suicidal ideation as an adverse effect, albeit rare, for finasteride tablets, particularly the hair loss dosage of 1 mg per day.
A man who experiences sudden depression, especially with thoughts of self-harm or suicide, should discontinue the medication and seek medical assistance as soon as possible. In particular, the latter has emergency services’ immediate attention.
Once again, this is not a reason to avoid the medication out of hand, but rather a warning to be aware of – particularly for men who already have a history of depression.
Does it affect fertility?
In some men, finasteride can reduce semen volume or negatively impact sperm count or quality. In most cases, these effects are reversed when the medication is discontinued, but men who already have fertility issues may not want to add further challenges. If a man is undergoing the treatment and considering parenthood, it is wise to consult a fertility specialist or a urologist.
Women who are pregnant or suspect they may be pregnant should not handle the medication or the crushed contents of the tablet – ideally, regular tablets, as they are coated to prevent such exposure. Exposure can affect a male fetus’s development.
Finasteride or minoxidil?
The two medications are largely different in their mechanisms and methods – they do not stack or synergize in any particular way. Finasteride prevents DHT from damaging the follicles by reducing its production, while minoxidil encourages existing follicles to prolong their growth phase.
As such, it is not uncommon for the two to be prescribed together. Some men prefer a single daily pill to twice-daily minoxidil applications. On the other hand, there are men who are particularly concerned about the potential sexual and psychiatric side effects of finasteride and choose the topical medication instead.
Before considering either, it is important to ensure that the diagnosis is indeed androgenic alopecia – sudden severe shedding, round or oval spots of total baldness, painful or itchy scalp, unusual scaling or flaking, and other strange symptoms may indicate a different condition. Our guide to alopecia types goes over the potential causes of hair loss in greater detail.
One final consideration is that PSA levels are reduced while on finasteride – the testosterone marker used to assess prostate health is lowered. If a man has his PSA tested while on the medication, it is worth mentioning it to whoever is reviewing the results.
Finasteride should be used as early as possible, when the follicles are still partially active – it will help to thicken the hair on the crown or allow it to maintain its existing density. It will cause the receding hairline to advance much more slowly. Sometimes, its most significant effect is that a year later, the man will look much the same as he did when he began the medication.
It is not exactly flashy, but for a chronic and progressing condition, it is often the best outcome a man can hope for – and that is something to consider.
