Tartaric Acid

Tartaric acid is an alpha-hydroxy acid used primarily for exfoliation and pH adjustment, typically around ~1–10% in leave-on products at an acidic functional pH. Like other AHAs, it can predictably cause stinging, erythema, and barrier disruption in sensitive or eczematous skin—especially when combined with other actives or used on compromised skin—so it warrants careful introduction and patch testing.