Differin Gel (Adapalene 0.1%)

This is the most useful thing on a drugstore shelf. Adapalene was prescription-only until 2016, and it's a genuine retinoid — the same class as tretinoin, working on the same receptors.

Retinoids are the only OTC ingredient that treats acne at the source: they stop pores from clogging in the first place, rather than cleaning up after they have. That means they treat blackheads and whiteheads as well as inflamed pimples — something benzoyl peroxide and salicylic acid don't do nearly as well.

Adapalene is also more stable and less irritating than tretinoin. It doesn't degrade in sunlight the way tretinoin does, and it's generally better tolerated — which is why it's the sensible retinoid to start with.

And it's a bonus anti-aging product. The same cell turnover and collagen stimulation that clears acne also softens fine lines. You're getting two treatments for about $15.

The purge is real. Skin usually gets worse for 4–12 weeks before it gets better — retinoids push existing clogs to the surface. Most people quit right here, which is exactly the wrong moment. Push through.

Start slowly. Twice a week, a pea-sized amount for the whole face, at night. Build up over months. Going daily from day one is how people conclude they "can't tolerate retinoids."

Expect dryness and flaking early on. Buffer it: moisturizer first, then Differin, then moisturizer again.

Wear sunscreen. Retinoids make skin more sun-sensitive.

Not safe in pregnancy. Stop if you're pregnant or trying.

Be patient. Give it 12 weeks minimum before judging.