Cathy inquires…I occasionally suffer from itchy scalp but this morning I was out of my usual Fructis dandruff shampoo so I used my roommates Head and Shoulders. The one in the dark blue bottle. I swear that my hair has smelled like rotten eggs all day. Why is that and why did this product cause it when others don’t? I thought all dandruff shampoos were essentially the same except for color and fragrance.
The Left Brain responds:
The majority of dandruff shampoos use zinc pyrithione (ZPT) as the active ingredient. For most people that’s sufficient to alleviate their symptoms. But the Over the Counter Drug monograph that controls the active agents that can be used in these shampoos includes other options for those people who don’t respond well to ZPT.
One of those options is selenium sulfide which works by reducing corneocyte production and an antifungal mechanism that is yet unknown. As many sulfur containing compounds do , selenium sulfide can have a residual sulfur odor that is very reminiscent of rotten eggs. The Clinical Strength variety of Head and Shoulders (the one in the dark blue bottle) uses this eggy ingredient. If your typical Fructis shampoo works for you stick with it and let your room mate be the egg head.
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Where I live- Greece- I never saw any H&S bottle having selenium sulfide as an ingredient. Only zinc pyrithione. That’s weird :I
@Christine: The regulations we’re quoting are for the U.S. It’s possible that this ingredient isn’t allowed in Greece or it could just be that H&S doesn’t market that version there. Most of the H&S products here are ZPT too.
The other thing I’ve noticed about ZPT is that is used in some antifungal medicine of external use. I’ve had over the years some issues with a very common type of fungal skin infection, i think the correct term would be
“motley dandruff” so my derm prescribed me lotions with that ingredient in concentration about 6%. Or less. And when I asked her about H&S and the fact that it is an OTC drug in US she replied that they- doctors like her- consider it just as a cosmetic. Nothing more or less…
Well that is a rather unpleasant smell. I would seek an alternative ingredient that is still effective but I am not aware of how many there are.
I used some expired “Selsun Blue” because I was desperate to get rid of the flakes. Now I smell like a dumpster. Rather would have had the flakes!! How long does it take for this smell to go away? Should I be washing my hair several times per day to help? Help!!!!!! I appreciate your advice!! Thanks!!
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