PABA and its esters are more waterproof than other sunscreens because they penetrate more deeply into the skin. Sunscreens may produce side effects. Those which use alcohol or ethanol bases frequently are drying and may burn the eyes. The moisturizing lotions may appear greasy and aggravate acne. Other side effects include irritation and allergy.
Irritation is most common in products with an alcohol base.
The most common allergen is PABA, although any sunscreen can cause sensitivity. Each person must find a sunscreen, by trial and error, which is acceptable. If the problem of allergy is difficult to solve, a dermatologist can help identify specific allergens by patch testing. PABA also tends to stain cotton, nylon, and polyester which may make it unacceptable. PABA does not absorb UVA and will allow tanning.