Salicylic acid and glycolic acid. Topical beta hydroxy acids (such as salicylic acid) and alpha hydroxy acids (such as glycolic acid) are effective over-the-counter acne treatments. Although they do not have FDA pregnancy safety ratings, they are considered safe during all trimesters of pregnancy and breastfeeding due to their negligible systemic absorption. One caveat is that pregnant patients should avoid topical application of salicylic acid to large areas for extended periods of time or under occlusive dressings to prevent increased systemic absorption. Glycol and milk peels are considered safe during pregnancy and lactation due to limited skin penetration.