Advantages Of Oral Vs. Topical Finasteride: A Comparison

Hair loss is a unique experience for everyone. It takes on many different sizes, shapes, timeframes and more, and just like hair loss itself, the treatments for it come in many various forms, some more researched than others, and work in many ways.

But there is one treatment that has separated itself from the rest and is well known for being one of the most effective treatments on the market: finasteride.

Typically, finasteride is taken orally, and a lot of people may not even know that it comes in a topical form as well. But why would they make a topical version? Are there any advantages?

Those are the questions we are going to be exploring in this article. By looking at the available evidence, we will be determining what the potential advantages and disadvantages are for each form of finasteride. But first, a quick synopsis of how finasteride works.

Finasteride overview

Finasteride is a type of drug classified as a 5-alpha reductase (5-AR) inhibitor.

5-AR is an enzyme that is responsible for the conversion of testosterone into dihydrotestosterone (DHT). For those who are new to the world of hair loss; DHT is the hormone that scientists believe is primarily responsible for androgenic alopecia (pattern hair loss). Blocking DHT is the most important thing to address when trying to overcome hair loss.

By blocking 5-AR, finasteride helps reduce the amount of testosterone that is converted into DHT and therefore helps stop the progression of hair loss.

Now that we have covered how finasteride works, we need to determine which form of it will give you the best chance of growing your hair back.

Oral vs. topical finasteride

Let’s look at some important criteria.


Like stated earlier, finasteride is normally taken orally and it is the much more popular of the two options. This is because oral finasteride is FDA approved, meaning that it had to undergo extensive testing and research (FDA approval is a rigorous process) showing that it was effective.

When taken at the 1mg or 5mg standard doses, it has been well established that finasteride can effectively block up to around 70% of DHT (1,2). It has also shown to work in about 60-80% of men that take it (3,4).

Unlike oral finasteride, topical finasteride is not FDA approved. This makes it much harder to obtain, means that there has been much less research done on it, and means that there has not been a standard dose established.

Unfortunately, current research on topical finasteride does not provide any baseline number to reference for how much DHT it blocks or its success rate. But, there have been several studies done that have shown it to result in improved hair growth (5,6,7). One study (8) even compared it directly to oral finasteride and found that they were equally as effective at maintaining hair.

Without an exact number to reference we cannot confidently say that topical is more or less effective than oral finasteride. Although because it has FDA approval and exact numbers to back it, oral finasteride takes the cake in terms of effectiveness (for now).

Side effects

Oral finasteride has a side effect profile that is well known and should never be ignored. Although the side effects occur rarely (between 2-4% of the time), some of them are potentially serious. The potential side effects include:

Lowered sex drive

Trouble keeping an erection

Skin rash

Ejaculation disorders

Swelling of the lips, tongue, or face

Nipple discharge


(Full list of side effects from the Mayo clinic here)

Luckily, even though the side effects sound serious, oral finasteride is usually very well tolerated and the side effects are usually reversible if you stop taking it (9).

Topical finasteride on the other hand may offer some benefits in terms of lowering the risk of potential side effects. This is due to the nature of a topical vs. oral drug: only a small fraction finasteride goes systemic when it is applied topically vs. taken orally (10). Although the evidence is limited, it is plausible that using topical finasteride may be able to mitigate the sexual side effects (11). But does that mean it is free of side effects? Not quite.

Subjects in several studies reported scalp irritation, increased liver enzymes, testicular pain, and headaches. In essence, based on current evidence, it may be possible that topical finasteride can decrease the chances of experiencing sexual side effects, but it seems there are still potential adverse side effects that can occur.

At this point, oral finasteride is again much more well-researched and the side effects are well documented and understood. Unless you want to take more of a risk of the unknown oral finasteride is the better route.

Availability in the U.S.

As if it isn’t already clear by now, oral finasteride is much easier to get than topical finasteride.

Since it is FDA approved, if you begin to experience hair loss, it is not difficult to obtain a prescription for finasteride tablets (online or in person).

Topical finasteride on the other hand may not be so easy to get. Its lack of FDA approval means that it cannot be made commercially available in the U.S., meaning that the only way to get it is through international retailers. This can become very expensive quickly and may not be trustworthy.

Whether you prefer oral or topical finasteride, the most important thing is that you choose a treatment that you can remain consistent with.

In conclusion

Topical finasteride shows a lot of promise for the future. There is some evidence suggesting that it may be equally as effective as oral finasteride, with the possibility of also minimizing the sexual side effects.

Overall though, currently oral finasteride is the better choice because it is much more well-researched. Until topical finasteride is further investigated, I would recommend sticking with oral, although if you do not respond well to it topical finasteride may be a viable substitute.

Just like a house needs a strong foundation, so does your hair.