Stemoxydine is a patented molecule by L'Oreal for hair loss treatment (see more detailed information about Stemoxydine here).  Stemoxydine 5% was shown to stimulate hair regrowth in a small scale 101 subjects clinic study.  L'Oreal stated that Stemoxydine is free of any side effects seen in minoxidil products.  This sounds too good to true. Is it really true?

Here is our thoughts.

1. Like any minoxidil products, all L'Oreal stemoxydine products (including “Kérastase Densifique Hair Treatment”, "L'Oreal professional serixyl dense hair treatment" , "Vichy Dercos Neogenic Hair Loss Treatment" and "Redken Cerafill Retaliate Stemoxydine Treatment") have high percentage of alcohol and propylene glycol, which are known to cause dry skin, scalp irritation, flaking, or danruff. 

2. The number of subjects used in L'Oreal's study is too small to detect some side effects. There were 101 subjects in the L'Oreal's clinical study, which means there was only 50 subjects who were given the stemoxydine and 50 who were given pacebo. The occurence of most of the minoxidil side effects is 2% or less. With that rate, you expect to see one or fewer case statistically but you may not see any case at all in reality. For example, when you toss a coin, you expect to see the tail 50% of the times. But if you just toss a few times like 2, 3, or 4 times, you may not see the tail at all. Another thing we need to keep in mind is that all the stemoxydine products are marketed as cosmetic products. The clinical data of cosmetic products do not face high scrutity as those of OTC drugs (such as minoxidil). There is no organization to approve cosmetic products, and nobody to examine its clinic study and safety information. 

3. Stemoxydine (aka, Diethyl pyridine-2,4-dicarboxylate) is a synthetic pyridine derivative. It affects some enzyme activities and creates a hypoxia environment to help stimulate hair regrowth. Our body is a very precise machine, if some of the enzyme activities are affected, it is very unlikely that it does not have any side effects. It is just a matter of how serious the side effects are, or whether they are reported or not.  

Having said so, the side effects of stemoxydine product are sure to be different from those of minoxidil. So it is worthy trying a stemoxydine based product if you are allergic to minoxidil itself. Please note that ~ 90% of people who are allergic to minoxidil products are actually allergic to propylene glycol not minoxidil itself. Thus using a Minoxidil product without Propylene Glycol is probably a better option.

If you want to avoid minoxidil, you can also consider ketoconazole shampoo or topical spironolactone products.