How can ointments help the skin?

Ointments are typically oil-based. Because they have little or no water or other liquid to evaporate, they tend to feel sticky and greasy and are less pleasant to use. They are useful however because they are very effective at helping to deliver the active ingredients, as long as the active ingredients can separate from the oil. The occlusive, or blocking, nature of ointments provides a water-proof barrier over the surface of the skin that helps to keep the skin hydrated by preventing water loss out of the skin. This hydration further enhances penetration of the active ingredient. That is why ointments are especially useful for skin that is dry and thick, like skin of the palms of the hands and soles of the feet, or for people who have psoriasis or eczema and who have thicker active lesions. By the same token, avoid greasy formulations if you tend to break out. Instead, look for products that are labeled as non-comedogenic or non-acnegenic.