NIC Esthetician Written ExamTreatment ProceduresHard
A client with Fitzpatrick skin type IV is undergoing a series of chemical peels to address hyperpigmentation. Which of the following ingredients should the esthetician be MOST cautious about using in high concentrations due to the increased risk of Post-Inflammatory Hyperpigmentation (PIH) in darker skin types?
- ASalicylic acid
- BMandelic acid
- CLactic acid
- DGlycolic acid
Show answer & explanationAnswer & explanation
Correct answer: D. Glycolic acid
Glycolic acid, with its small molecular size, penetrates deeply and rapidly, increasing the risk of inflammation and subsequent PIH in darker skin types (Fitzpatrick IV-VI) if used in high concentrations or aggressively. Lactic and Mandelic acids are generally safer due to larger molecular size and slower penetration.
Why the other options are wrong
- A. Salicylic acid is a BHA, effective for acne, but its PIH risk is generally lower than high-concentration glycolic acid for its anti-inflammatory properties.
- B. Mandelic acid has the largest molecular size among AHAs, making it very gentle and suitable for darker skin types with less PIH risk.
- C. Lactic acid has a larger molecular size and is generally gentler, posing less risk of PIH.
Post-Inflammatory Hyperpigmentation (PIH)
Darkening of the skin that occurs after an inflammatory injury or trauma to the skin, common in darker skin types.
- More prevalent in Fitzpatrick skin types III-VI
- Can be triggered by aggressive treatments or sun exposure
- Important consideration when selecting chemical peel types
Memory trick: Glycolic's Grip Gets Deep, PIH can Leap.