How do you cure dry scalp (not dandruff) when you've tried every dandruff shampoo there is?

My boyfriend has had it for years, and although it doesn't bother me, he's very self conscious about it. He's very hygienic also, so it's not like he doesn't shower. He's tried all kinds of shampoos but to no avail.How do you cure dry scalp (not dandruff) when you've tried every dandruff shampoo there is?
He should not wash with shampoo every time he showers. Only ever other time. He should just shower with warm water, not hot. Try aloe plant, i just cut a limb in half and rub it all over my scalp. If you have trouble finding this plant, then you could buy a bottle of 100% aloe. It is also good to use tea tree oil before showering.How do you cure dry scalp (not dandruff) when you've tried every dandruff shampoo there is?
he might try olive oil

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