Mandelic acid, an alpha-hydroxy acid (AHA), named after the German mandel (almond) and derived from the hydrolysis of an extract of bitter almonds has been extensively documented for its effectiveness in treating common skin problems, such as photo-aging, irregular pigmentation, blemishes, congested skin and acne. In ethnic skin, studies have shown that mandelic acid is useful in suppressing pigmentation, treating inflammatory non-cystic acne, and rejuvenating photo-aged skin, doing so safely, without causing skin discoloration.