Desitin Original Ointment 16 oz Jar Rich, Thick and Effective Desitin Original Ointment is formulated with 40% zinc oxide, in a base of cod liver oil (rich in Vitamins A and D), lanolin, and petrolatum. Its rich, thick formula stands up to diaper rash, providing long lasting protection against wetness and irritants. Desitin is so effective, in fact, in a clinical study, 90% of babies with diaper rash had noticeable relief within 12 hours with use of Desitin Original. And because Desitin is hypoallergenic, it"s gentle on your baby"s tender skin. That"s a relief for your baby - and you.