The current Head and Shoulders is awful. It practically burns your scalp off.
Researchers working for the maker of Head and Shoulders anti-dandruff shampoo have mapped out the genome of the microbe that causes the pesky condition. The news is being hailed as a breakthrough that could put millions of snowy-shouldered people out of their misery, according to a report in The Sunday Times newspaper. …
A one off application won't clear you for good, the fungus is likely to remain in existance somewhere.
So, they produce a treatment wash in small, over priced bottles, and continue making a moisturising / conditioning shampoo for regular use.
The treatment may keep the fungus at bay for a few months or even years, but it is likely to return every so often.
FWIW, it doesn't help with the dandruff, but a handy hint to blokes. I quit using shampoo a few years back, so now I just rinse my hair well instead. At the time my hair was going thinner and receding fast - wodges of hair needed removing from my brush every week. Without shampoo, my hair is tons thicker, the hair in my hairbrush just quit appearing, and my hairline stopped heading north. Apparently top models don't use whatever fancy shampoo they're promoting either, they just rinse their hair. Same principle as why you don't shampoo animals too often as well.
And best of all it gives you carte blanche to use the Jasper Carrott gag: "Wash and Go. I washed it - it went." Ba-dum-ching!
... when a naturally-occurring mutation or a lab goof creates a resistant strain of Mala-simon-sez-ia? We're already seeing what happens when something ubiquitous like Staph. aureus develops multi-drug resistance.
I can just picture it now: scientists tweak the genetic code of dandruff fungus and the resultant strain is no longer content to feed on just the surface of our scalps.
Hey, Tobe Hooper! I'll sell ya the movie rights!