As skin-care ingredients go, adapalene (like the popular over-the-counter option Differin) and its prescription cousin tretinoin have a lot in common. Both are retinoids—vitamin A derivatives ...

Topical retinoids (for example, tretinoin) and retinoid analogues (for example, adapalene and tazarotene) help normalize hyperkeratinization and have demonstrated significant anti-inflammatory ...

For over-the-counter retinol, it can take up to six months and with tretinoin up to three months for full results to be visible. With retinoids, it’s often a “worse-before-better” type of ...