DMDM hydantoin is an antimicrobial formaldehyde releaser preservative with the trade name Glydant. DMDM hydantoin is an organic compound belonging to a class of compounds known as hydantoins. It is used in the cosmetics industry and found in products like shampoos, hair conditioners, hair gels, Rite Aid Liquid Lubricant, and skin care products. DMDM hydantoin works as a preservative because the released formaldehyde makes the environment less favorable to the microorganisms.