Adapalene can come in either over the counter or prescription formulas, and is actually the only retinoid medication that can be purchased without a prescription in the United States (via Healthline). It has been highly studied by dermatologists, with one statistic showing that 74% of adapalene users saw a decrease in acne induced inflammation upon application. One benefit of adapalene is that it tends to be less irritating to the skin than most retinoids, making it ideal for those with sensitive skin.

For tretinoin, this powerful FDA approved retinol can only be prescribed by a doctor. It works by increasing the rate of skin cell turnover, clearing off dead skin cells more quickly. This opens your pores and releases acne causing bacteria, and can take about 12 weeks to see results. Although tretinoin treats breakouts and acne scars, its highly rapid cell turnover rate can result in blistering, redness, and more.

Even though tretinoin is a stronger formula when it comes to preventing and treating acne than adapalene, its irritating and drying side effects may not be for everyone, especially those with sensitive skin. Dermatologist Tiffany Libby told Mind Body Green that it is a misconception that tretinoin is superior to adapalene just because it is the stronger option. "Adapalene is perceived to be less efficacious, but in reality, studies suggest that it has similar efficacy to tretinoin, just with better tolerability," she said.