Isopropyl Myristate is best treated as a cautious avoid during an active seb derm flare or in a strict Malassezia-conscious routine. It is an isopropyl ester of myristic acid, used mainly for texture, softness or spread. Laboratory work found that Malassezia can hydrolyse isopropyl esters and use some released long-chain fatty acids. That creates a theoretical concern, but it does not show that every finished product containing Isopropyl Myristate will cause a flare.

Raw-ingredient culture tests cannot reproduce a complete cosmetic on human skin. Concentration, product format, other ingredients and the Malassezia species present can all change the result. If you want the simplest approach during a flare, choose a formula without Isopropyl Myristate; otherwise stop if repeated use increases itching, redness, tightness or stinging.