Porosity Nerd

Pilling is a layering problem, not a product quality problem, and there are three levers.

Wait time first. Most people give it 30 seconds and a humectant serum needs three to five minutes to actually absorb rather than sit as a film.

Quantity second. Hyaluronic serums are the worst offender for over-application. Four drops does nothing more than two.

Third, stop rubbing the sunscreen in. Press and pat it on in sections. The rolling is your fingers shearing the layer underneath.

If all three fail, that specific pair is incompatible, usually a silicone-heavy sunscreen over a gel, and swapping one is the fix.

Almost certainly. Park it entirely for a month, then reintroduce at most once a week if you still want it.

Cheekbones flaking at six weeks usually means frequency, not strength. What worked for me after two failed starts was dropping to twice a week for three weeks and sandwiching it: plain moisturiser, wait ten minutes, tretinoin, wait ten, moisturiser again. That blunts the peak irritation and the flaking settled inside a fortnight.

Also look at what else is in the routine. An exfoliating acid, a vitamin C, or a foaming cleanser with sulphates is usually the actual culprit and the tretinoin gets blamed. Strip back to cleanser, moisturiser, tretinoin, sunscreen for a month.

This is just what got me through it, and your prescriber is the right person to check the plan with.

The cheap one you apply properly, every time, and it isn't close. Performance is dominated by how much you put on. The tested figure assumes a genuinely thick layer, and applying half of it does not give you half the protection, it gives you considerably less than half. A rationed premium bottle is the most common way people end up under-protected while feeling careful.

The only thing worth holding out for is a texture you'll tolerate daily, because a sunscreen you skip is worth zero at any price. If the supermarket one feels acceptable, buy it in bulk and stop thinking about it.

The heuristic that has held up for me: purging is faster in and faster out, in your usual places, and it's the same kind of spot you normally get, just more at once. New locations plus a new shape, small uniform closed bumps rather than your usual chin spots, reads more like irritation or a comedogenic reaction. Three weeks is at the outer edge of plausible purging and still getting new ones is the part I'd weigh most.

What I'd do: stop for two weeks, change nothing else, and see. If it clears, reintroduce every third day. If it doesn't clear, it was never the azelaic acid and you've learned something more useful.

If it becomes painful or spreads, that's a dermatologist conversation rather than a forum one.

Ten seconds that fully resolves, on skin you've said is compromised, usually means the barrier isn't intact yet rather than the product being wrong. Things that would normally sit on the surface are reaching places they shouldn't.

The test is whether it's shrinking week over week. Mine went from about fifteen seconds to nothing over three weeks on a bland routine. Same or worse at week four, or redness and itch afterwards, is a different thing and I'd stop.

Meanwhile: no acids, no retinoids, no scrubs, lukewarm water, and give it real time. Over-exfoliated skin takes far longer to come back than it took to break.