This product can cause burns. 55 Or older: your risk of burning increases as you age. Do not wear while sleeping. Check skin frequently during use. If you find irritation or a burn, remove product immediately. Do not use if heat cell contents leak and/or wrap is damaged or torn; for more than 8 hours in a 24-hour period; with pain rubs, medicated lotions, creams or ointments; on unhealthy, damaged or broken skin; on areas of bruising or swelling that have occurred within 48 hours; on areas of the body where you can't feel heat; with other forms of heat; on people unable to remove the product, including children, infants and some elderly; on people unable to follow all use instructions. Ask a doctor before use if you have diabetes; poor circulation or heart disease; rheumatoid arthritis; or are pregnant. When using this product check skin frequently for signs of burns or blisters - if found, stop use; if product feels too hot - stop use or wear over clothing; do not place extra pressure, a tight waistband or belt over the product; to avoid increased risk of burns, remove product before undergoing any mri (magnetic resonance imaging) procedures. Stop use and ask a doctor if pain worsens or persists for more than 4 days; if you experience any discomfort, burning, swelling, rash or other changes in your skin that persist where the wrap is worn. Keep out of reach of children and pets. Each heat cell contains iron (-2 grams): can be harmful if ingested (if ingested, rinse mouth with water and call a poison control center immediately); if heat cell contents come in contact with your skin or eyes, remove wrap, rinse affected area with water and seek professional assistance immediately. Do not microwave or attempt to reheat as wrap could catch fire.