Which of the following statements about creams and ointments is true?

Ointments are composed of a higher proportion of oil or fat compared to creams, which typically have a higher water content. This formulation allows ointments to create a more occlusive barrier on the skin, which means they adhere better and remain in contact with the skin surface for a longer period. As a result, ointments can provide prolonged delivery of the active ingredients, making them effective for conditions that require sustained treatment.

In contrast, creams, being more water-based, tend to absorb more quickly and may evaporate or wash away from the skin more easily, leading to shorter periods of effectiveness. This property of ointments is particularly beneficial for maintaining moisture in dry skin conditions and for topical medications that require longer contact time to achieve their therapeutic effects.