Prioritize a patch test if you have known allergies. When applying our pen eyeliner, avoid over-shaking and excessive pressure to preserve the fine tip. Secure the cap tightly to prevent drying, and store the product upright to maintain consistency. While water-resistant, prolonged water exposure may impact longevity. Refrain from applying directly to the waterline to prevent irritation. If you encounter any discomfort or adverse reactions, discontinue use. Always check the ingredient list for potential sensitivities.