Minoxidil is one of only two treatments approved by the FDA to treat hair loss. Trials of minoxidil have tested the effectiveness of 2% and 5% solutions and found the stronger concentration significantly improves hair regrowth. This raises the question: could a stronger minoxidil solution – such as 10% – produce even better results?
What is minoxidil?
Minoxidil is a medication that is applied topically to the scalp. It slows hair loss and in many people actually causes hair regrowth.
Originally developed to treat high blood pressure, the hair-regrowing effects of minoxidil were discovered by accident. Patients treated for hypertension reported unexpected hair growth from minoxidil, and in 1988 a 2% topical version was approved to treat androgenetic alopecia (pattern hair loss).
In the announcement, the FDA noted that around 39% of men had “moderate to dense hair growth on the crown of the head” – and this was only from the 2% version.
You might have heard of Rogaine – the most popular brand of minoxidil. In 1996, Rogaine’s patent for minoxidil expired, allowing other manufacturers to start producing their own versions. A year later, a 5% version of rogaine was introduced.
Linear dose response
So how did the 5% version compare to the original?
This study compared the ability of the two formulations to regrow hair:
“In men with AGA, 5% topical minoxidil was clearly superior to 2% topical minoxidil and placebo in increasing hair regrowth, and the magnitude of its effect was marked (45% more hair regrowth than 2% topical minoxidil at week 48). Men who used 5% topical minoxidil also had an earlier response to treatment than those who used 2% topical minoxidil. Psychosocial perceptions of hair loss in men with AGA were also improved. Topical minoxidil (5% and 2%) was well tolerated by the men in this trial without evidence of systemic effects.”
So not only was 5% minoxidil more effective than 2% minoxidil, it was much more effective.
This shows that it’s dose dependent – at least at this level. The higher concentration of minoxidil, the more hair regrowth. Not only that, it takes less time to start seeing results.
So, is 10% minoxidil more effective than 5%?
Unfortunately, there have been no clinical trials of minoxidil solutions greater than 5%.
But the differences between the 2% and 5% formulations suggest that a higher concentration would indeed be more effective. What’s more, there are plenty of anecdotal reports online supporting the benefits of higher strength minoxidil.
That said, in the trials of 2% and 5% formulas, hair regrowth wasn’t directly proportional to the concentration of minoxidil. Higher concentrations did indeed produce better results, but just because 10% minoxidil is twice as strong as 5%, this doesn’t guarantee you’ll regrow twice as much hair!
Nevertheless, it is reasonable to expect a 10% minoxidil solution to produce significantly superior results to both 2% and 5% concentrations.
So what about even stronger solutions? 15% minoxidil? 20%? 25%?
Unfortunately, there is a limit to how concentrated these solutions can be.
Minoxidil, in its powder form, can’t be absorbed by the skin. Instead, it first needs to be dissolved into a liquid or foam vehicle. Commonly used vehicles – such as propylene glycol and ethanol – can only dissolve around 100mg of minoxidil per 1ml. This makes it difficult to make concentrations above 10% without having excess minoxidil powder floating in the solution.
What about side effects?
As drugs go, minoxidil is about as safe as they come. And because of this excellent safety profile, minoxidil is available over-the-counter.
But some users do report negative side effects from minoxidil use. The most common of these are dry scalp, irritation, and redness. Usually, though, these symptoms are a response to inactive ingredients rather than minoxidil itself. Alcohol and propylene glycol, for example, can cause irritation if you have particularly sensitive skin.
So, a higher concentration of minoxidil doesn’t make these symptoms more likely. It does, however, increase the risk of systemic minoxidil absorption.
As a topical treatment, it’s very rare for minoxidil to make its way into the blood stream. However, if this does happen, it can lead to pretty serious side effects such as dizziness, fainting, or rapid and irregular heartbeat.
Again, these side effects are very rare. But if you’re using a derma roller as part of you hair regrowth regimen, it can make them more likely. Wait at least 24 hours to use minoxidil after microneedling and if you experience any of these symptoms, discontinue use immediately. Also, only apply minoxidil to a dry scalp to reduce the chance of systemic absorption.
10% minoxidil vs 5%
Minoxidil doesn’t work for everyone. But if you do respond to 5% minoxidil, you’re likely to see even better results with the 10% formula.
And because of minoxidil’s excellent safety profile, more concentrated versions are unlikely to cause negative side effects.
However, it’s not a miracle cure. For one, minoxidil does nothing to reduce DHT levels – the hormone responsible for hair loss.
But minoxidil is one of the only hair loss treatments that can actually regrow hair. And when used in conjunction with drugs that reduce DHT levels – such as finasteride or dutasteride – it can lead to some pretty impressive results.