Clear answers about dark spots.

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• Cysteamine for Dark Spots: What It Is and What Studies Show

  Cysteamine is a small sulfur molecule your body already makes.

• Hydroquinone-Free Options for Melasma: What Has Evidence?

  People who want to avoid hydroquinone usually ask the same question: what else has evidence behind it?

• Cysteamine vs Hydroquinone for Melasma: What the Trials Actually Found

  Short version: across the pooled reviews, the estimate favored 5% cysteamine versus placebo.

• Melasma, Sun Spots, and Post-Inflammatory Dark Spots: What Is the Difference?

  "Dark spots" is a description, not a diagnosis. Three different things get called that, and they behave differently.

• When Did Studies of Other Cysteamine Creams Measure Changes?

  The published trials cited here ran 12 weeks, 16 weeks, or four months, with scheduled checkpoints along the way.

• Cysteamine Side Effects: Odor, Tingling, Redness, and Dryness

  In the published studies, the side effects people reported were redness, burning, itching, irritation, and dryness. Some people also notice a sulfur smell.

• The History of Cysteamine: From a 1966 Observation to Modern Pigment Creams

  Cysteamine's skincare story starts in a laboratory, with fish.

• Can You Use Cysteamine With Retinol, Vitamin C, Acids, or Hydroquinone?

  The Illuminate Rx formula already contains glycolic acid, retinol, and two forms of vitamin C. That's worth knowing before you add anything else to your routine.

• Cysteamine With Peels, Lasers, or Microneedling: Questions to Ask First

  The evidence for combining cysteamine with a procedure is thin.

• Why Melasma Comes Back: Sunlight, Visible Light, Hormones, and Maintenance

  Melasma comes back because it's a chronic condition with several drivers, and clearing a patch doesn't remove any of them.