Formula does make a difference, but which one is right for acne-prone skin? Cream moisturizers have more fats and oils in them (called lipids) and are intended for dry skin. A lotion or serum is a better choice for skin that tends to break out, especially if it's labeled non-comedogenic or non-acnegenic. It will feel lighter, too -- even on oily skin. If the moisturizer you choose doesn't cause breakouts but still feels heavy, mix a little water into the moisturizer in your palm before applying.
For acne-ridden skin that's also very dry and flaky (a common reaction to acne medications), a heavier -- but still non-comedogenic -- cream may be appropriate. "It's particularly important that patients maintain moisture balance when using acne products, especially topical vitamin A, as it exfoliates and may dry the skin," says Goodlerner.