Tretinoin, retinal, retinol and adapalene: a practical map
The family name helps organize the shelf; the exact molecule tells you what you are comparing.
The reference desk
A plain-language reference for percentages, claims, tolerability and the questions worth taking to a clinician.
Advertising disclosure: CoreAge Rx is our featured commercial partner and appears first. Placement is promotional; it is not a clinical superiority ranking. How we are funded
Why retinoid percentages are not a universal strength ladder
A decimal point only becomes useful when the ingredient and formulation are known.
Irritation is a reason to reassess, not a score to chase
Understand how tolerability affects the usefulness of a retinoid plan.
How long should a retinoid claim take to make sense?
A laboratory conversion rate, a hydration change and a clinical outcome run on different clocks.
Retinoids and pregnancy: review the routine before choosing
Prescription and cosmetic status do not remove the need for pregnancy-specific advice.
A retinoid price check that compares the whole offer
The monthly headline, delivered quantity and clinical access should appear on the same page.