What is paradoxical hypertrichosis in laser hair removal, and how is it managed?

• A. Unexpected new hair growth in treated areas; prevent with proper energy settings and cooling; manage by adjusting the treatment plan or pausing if it occurs.
• B. Temporary loss of hair in treated areas.
• C. Permanent skin scarring.
• D. Immediate skin discoloration in surrounding skin.

Answer: (B)

Paradoxical hypertrichosis is the unexpected regrowth or thickening of hair in the area that was treated with laser hair removal. It’s the opposite of what you usually expect from laser work, where hair counts go down.

Management centers on preventing and mitigating this response. That means using conservative energy settings tailored to the patient’s skin type and hair, ensuring effective cooling to limit heat buildup, and adjusting the treatment plan if the reaction occurs—this can involve pausing treatments, re-evaluating pulse duration or spot size, and possibly spacing sessions more apart or changing the regimen altogether. The goal is to reduce follicular stimulation that could trigger new hair growth.

The option describing temporary loss of hair reflects a different, more typical immediate outcome after laser treatment (hair shedding or temporary thinning) and does not capture the paradoxical growth pattern. Permanent scarring or immediate surrounding skin discoloration describe other risks unrelated to paradoxical hypertrichosis.