7. Mineral Oil
Mineral oils have been shown to be effective when applied topically to the area. Note that this was specifically useful in cases where the psoriasis forms plaques.
Along with this, other moisturizers have similarly been found to be effective and these include salicylic acid, petroleum jelly, calcipotriol and decubal (which is an oil-in-water emollient). Emolients are also shown to be even more effective when they are combined with phototherapy.
Once again, combining any of the approaches on this list should result in enhanced benefits.