For a pop-culture name, I'd call it the Head & Shoulders Problem, after those old shampoo commercials:
"You use Head & Shoulders? But you don't have dandruff!" "Exactly!"
"You use Head & Shoulders? But you don't have dandruff!" "Exactly!"
Dandruff shampoos work by killing the fungi. There are three main types of anti-fungals, zinc pyrithione is used in Head and Shoulders, selenium disulfide in Selson Blue. There is a third one not commonly used called ketoconazole that you may want to try.
There is also coal tar shampoo, which is not an anti-fungal, instead it slows skin cell growth and sloughs off the dead skin.
Selson Blue works well for me, I use it daily. If I go off of it for a few days the dandruff kicks into high gear.
The thing about dandruff shampoos is you have to use them with a certain regularity because even if you kill the fungi, the condition takes a few days to clear up, the damage to your scalp is done. You need to create a hostile environment for the microorganisms, and that takes time.
Your dandruff is probably caused by only one type of organism that thrives in particular climates. Next time you're there, you might get ahold of two or three shampoos and try them for a week each and see if it clears up. Then you know which is 'your' anti-fungal.
Some problems aren't worth trying to fix.
"DANDRUFF: The ANSWER is usually vinegar. To some problems there are solutions.
"What we call dandruff is often the result of a PH imbalance on the skin, which shampoo exacerbates. Wash your hair with a simple non-detergent shampoo, soap, olive oil, beer, almost anything. Rinse. Then close your eyes and pour on some vinegar. The extremely cheap but natural sort—apple cider, for example—is probably best. The smell will stimulate interesting conversations in changing-room showers and your explanation will win you friends. Wait thirty to sixty seconds. Rinse it off. The smell will go away. So will your dandruff.
"All dermatologists, pharmacists and pharmaceutical companies know this simple secret. They don’t tell you because they make money by converting dandruff into a complex medical and social problem. By most professional standards this would amount to legally defined incompetence or misrepresentation.
"Dandruff shampoos that promise to keep your shoulders and even your head clean are harsh detergents and may promote baldness, which ought to constitute malpractice."
Sure, dandruff and 'dry skin flakes' are separate things entirely.
Dandruff is generally regarded to be caused by the fungus Malassezia. This fungus does not enjoy an acidic environment.
(Healthy) human skin tends towards pH 4-5 (there seems to be some debate). Malassezia likes 5-8 (again, some debate). Reducing the pH / increasing the acidity would appear to have some non-psuedo, non-alternative-medicine, non-falsehood foundation.
If the latter, I can probably agree. If the former, please do some more research.
https://www.urmc.rochester.edu/encyclopedia/content.aspx?con...
Maybe that's because vinegar isn't a staple in the hair care aisle at Walgreen's.
I'd be curious to know your results, in any case. I've had mixed outcomes from conventional (commercial shampoos) and have also been trying to identify causal factors (worse in winter, especially after a few days of wearing a beanie, worse when I'm staying near a high-pollution area, etc). It's all anecdata, but OTOH not beyond our abilities to thoughtfully analyse.
So far, my experiments with other shampoos where conducted a bit ad hoc. They're all anecdata. When I try with vinegar, I should try to rule out other causal factors first. I probably haven't done that in my first try. Otherwise, we can never be sure.
Not my wisest moment. I should probably have seen another dermatologist.