Even too much of a good thing can be bad, and that rule applies to acne spot treatments, too. This is especially true with over-the-counter treatments containing benzoyl peroxide and salicylic acid.
"The tendency is to apply them liberally, which will only make the surrounding skin red, dry, and irritated," said Shari Marchbein, MD, New York City-based board-certified dermatologist and clinical assistant professor of dermatology at NYU School of Medicine. "Instead, if you are going to spot treat, apply only a very thin layer one or two times per day maximum."
If nothing seems to be working or your acne is leaving you with scars or hyperpigmentation, that's when it's time to seek care from your doctor.