A chemical peel with low pH should be avoided in clients who use which medication?

• A. Ibuprofen
• B. Acetaminophen
• C. Retin-A
• D. Vitamin C serum

Answer: (C)

Low pH chemical peels cause strong exfoliation by acids, and a retinoid like Retin-A already makes the skin more sensitive and prone to irritation by increasing turnover and thinning the barrier. Combining a very acidic peel with Retin-A can lead to excessive irritation, burning, redness, and potential pigment changes. That's why this peel should be avoided for someone using Retin-A. Ibuprofen or acetaminophen don’t alter skin sensitivity to peels, and while Vitamin C serum is acidic, it doesn’t create the same level of heightened exfoliation risk as a retinoid, so it’s not the contraindicated medication in this context.