This wonder drug treats a host of common skin problems, including fine lines, age spots, and acne. "Tretinoin has the most science behind it in terms of eradicating sun damage and photoaging," says Ron Moy, MD, the president of the American Academy of Dermatology and a professor of dermatology at the David Geffen School of Medicine at UCLA. "There's also some evidence that it prevents precancerous lesions."
Tretinoin — most popularly prescribed as Retin-A and Renova — works its magic by speeding cell turnover and stimulating collagen production, which rejuvenates skin. "Retin-A is the gold standard," says Fusco. "If I could use only one thing, it would be that."