Cited skincare — every flag names its source, no upsell.The evidence, graded
expert consensusUse sunscreen every day with hydroquinone — every source Drop has read says so. UV-B, UV-A and visible light stimulate melanocytes, and repigmentation may occur following sun exposure, so concurrent use of sunscreen is required and photoprotection is a key to maximizing the benefit of hydroquinone use. The review adds that there are no clinical trials to support its therapeutic benefit. Neither clinical source names an SPF number — the 30+ floor is the AAD's melasma guidance.Schwartz 2026 · StatPearls [Internet] ↗ expert consensusHydroquinone is absorbed through skin at 35–45% — much higher than most topicals. Pregnancy and breastfeeding guidance is to avoid it, even though existing studies have not shown harm.Bozzo 2011 · Canadian Family Physician ↗ expert consensusHydroquinone is described as the gold standard for melasma, used at 2–4%, and works better in combination than alone. Improvement typically takes several weeks to months. The monograph puts a course at up to 3 months, with a stop if nothing has improved by 2 to 3 months, then several months off. Exogenous ochronosis is the debated risk: one review counted 22 US cases in over 50 years, across more than 10,000 supervised exposures. Daily sunscreen is part of the treatment.Sarkar 2014 · Indian Dermatology Online Journal ↗ Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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