BLOOD MenstruHeat Menstrual Heat Patches 2pcs. One retail pack containing two single-use, air-activated menstrual heat patches. Attach each patch to underwear as shown on the original package. Directions: Open the individual pack and attach the patch to underwear. Wait about five minutes for it to warm. After each hour of use, remove the patch for at least five minutes to let the skin rest. Remove immediately if it feels too hot. Do not attach directly to skin. Warnings: May cause burns after prolonged contact. Do not use while sleeping, on sensitive or red skin, or directly on skin. Check skin frequently and remove immediately if irritation or blisters occur. Ask a doctor before use if pregnant, diabetic, arthritic, or affected by heart disease or poor circulation. Do not use on skin that cannot feel heat properly, on infants, young children or elderly people. Do not put pressure on it or tighten a waistband over it. Do not ingest or microwave. Do not use on wounds, rashes, damaged or swollen skin, or where medication has been applied. Do not open before use. Keep out of reach of pets and children.