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Heat Therapy

  • The ThermaCare® Menstrual HeatWrap, Neck, Wrist & Shoulder HeatWrap, and Knee & Elbow HeatWrap are available in one size only. The Lower Back & Hip HeatWrap is available in S/M and L/XL sizes:


        Women's Pant Size    Men's Pant Size 
      S/M    Up to size 8    Up to 34-inch waist 
      L/XL    Size 9 up to size 20     35-inch 47-inch waist  

    Some retailers may carry one size most while other retailers may carry both the S/M and L/XL options.


  • The heat cells are the part of ThermaCare® that provides warmth. These cells contain a mixture of ingredients that react with air to provide low-level heat. The chemical reaction is called iron oxidation, which occurs naturally in the environment.

  • ThermaCare® was designed to provide heat therapy for long-lasting, powerful pain relief and relaxation of tight muscles. Because of the technology, each HeatWrap can be used only once.

    ThermaCare® works by using iron particles which, when exposed to air, start reacting. This reaction gives off heat, but once the iron is used up, it can’t be reactivated or recharged. So after the product stops heating, it won’t reheat and should be disposed of properly. ThermaCare® should not be used in microwave ovens, as the heat wrap may catch on fire.

  • Place the darker side of the heat cells against your skin. The product may not warm up as efficiently if you put the wrong side against the skin.

    • Lower Back & Hip: Place the HeatWrap against your back, centering the heat discs over the area of pain. The overhanging "flap" below the heat discs will be the bottom edge of the HeatWrap.
    • Menstrual: Remove the peel paper from the adhesive and attach the ThermaCare® Menstrual HeatWrap to the inside of your cotton or nylon underwear over the area of pain. Use your hand to press the HeatWrap into place to make sure it sticks completely. Note: The adhesive may not stick well if it has been removed and reattached to clothing several times.
    • Neck, Wrist & Shoulder: Remove the peel paper from the adhesive tabs and place the heat discs over the pain area. Press the adhesive tabs onto your skin. Note: Adhesive will stick better if skin is dry and free of oils or lotions.
    • Knee & Elbow: Remove the peel paper from the adhesive tabs. Bend knee (or elbow) slightly and place opening over kneecap (or elbow). Press the adhesive tabs onto your skin. HeatWrap straps around knee (elbow) and fasten. Note: Do not place heat cells on the back of the knee or inside the bend of the arm.

  • ThermaCare® HeatWraps are made from cloth-like materials called “nonwovens” and are the same materials used in disposable products like diapers and feminine hygiene pads. The wraps are held together by heating, and by glue that does not contain latex.

  • Each heat disc is designed to heat to about 104°F (40°C) for 8 hours. This temperature is just above your body's normal core temperature of 98.6°F.

  • Iron reacts with oxygen in the air to provide heat in a process called iron oxidation.

    • Sodium chloride (salt) speeds up the rate of reaction between iron and oxygen
    • Sodium thiosulfate controls hydrogen generation
    • Water also is necessary for the iron oxidation reaction
    • Charcoal allows the iron powder to have a surface to react inside the heat discs. The surface of this charcoal has been treated (activated) to have special properties
    • Sodium polyacrylate controls the level of water present in the heat cell
  • No, definitely not. Cutting the HeatWrap may damage the heat cells. Damaged heat cells can lead to increased risk of burning, and we do not recommend using a HeatWrap that has damaged or cut heat cells. If the HeatWrap is damaged or ruptured, contain the contents and dispose of it properly. If ingested, rinse your mouth with water and call a Poison Control Center immediately. If the heat cell contents come in contact with your skin or eyes, rinse right away with water and call a Poison Control Center immediately.

  • ThermaCare® has been thoroughly tested for safety, and most people will be able to use it without experiencing any discomfort. However, like any heating product, there is a risk of prolonged skin redness or burns for some people. Your risk of burning increases as you age. Use products as directed.
    ThermaCare® should not be worn for more than 8 hours in one day or more than 7 days in a row (4 days for ThermaCare® Menstrual). Check skin frequently during use. If you find irritation or a burn, remove the product immediately. Please see packaging for complete safety information and usage instructions.

  • You can safely wear more than one ThermaCare® HeatWrap, but do not wear more than one HeatWrap in the same location. Take precaution not to overlap heat cells or wear any HeatWraps under tight-fitting clothing, belts or waistbands. Check your skin frequently during use, and if you find irritation, stop use immediately.

  • You should consult with your doctor if you are pregnant and are experiencing pain and intend to use any pain relief products, including ThermaCare®. Your doctor will be able to advise you on your specific circumstance and can determine whether ThermaCare® is right for you at this time.

  • For best results, wear ThermaCare® for the full 8 hours. Using ThermaCare® for more than the recommended time can increase the risk of skin irritation or burns. ThermaCare® shouldn’t be used more than 7 days in a row; ThermaCare® Menstrual shouldn’t be used more than 4 days in a row. If during or after this time the pain you’re treating remains unchanged or worsens, consult your doctor, as this may be a sign of a more serious condition.

  • ThermaCare® has warmed up when it feels warm to the touch. Extensive testing has shown that ThermaCare® heats to about 104°F (40°C) within 30 minutes and maintains this temperature for 8 hours.

  • ThermaCare® has been designed to deliver a comfortable, well-controlled level of heat. Of course, this does not mean that it is the right amount of heat for everybody. Stop use and check skin frequently. You may want to try wearing ThermaCare® over a thin layer of clothing instead of directly against your skin. If you still feel the level of heat is too high, you might want to discontinue use of the product.

  • No. ThermaCare® doesn't contain magnets.

  • ThermaCare® can be disposed of in your regular trash. To be safe, dispose of it 8 hours after it is out of the primary foil package (or 12 hours later for Knee & Elbow products). Care should be taken to keep ThermaCare® out of the reach of children and animals.

  • The fastening adhesive on the ThermaCare® Menstrual HeatWrap wasn’t designed to be attached to the skin. For ThermaCare® Menstrual to heat effectively, it should be attached to clothing so the dark sides of the heat cell are against your skin. Do not apply the adhesive to your skin; it may result in irritation. Also, the device may not work properly if applied incorrectly.

  • If you have sensitive skin, check every couple of hours or anytime you feel discomfort. If your skin looks or feels as if it might be burning or irritated, remove the HeatWrap. It’s normal to notice slight redness immediately after removing the HeatWrap. Always read the package insert before using the product.

  • No. ThermaCare® HeatWraps aren’t recyclable. Recyclable products, like paper, plastic and glass, fall into a single material category. ThermaCare® is made from several different materials, which means recyclers won’t accept them.

  • No. Any attempt to reheat the product in a microwave oven can result in a fire.

  • No. ThermaCare® doesn't contain latex.

  • Diabetes is a complicated disease that sometimes causes poor blood circulation and decreased skin sensitivity and feeling. Since some diabetics may be more susceptible to skin irritation, skin injury or even burns than others, they first should consult with their doctor to determine if ThermaCare® is right for them.

  • Don’t wash or moisten a ThermaCare® HeatWrap because it will deactivate the heat discs. While excessive moisture or wetness will affect the ability of the heat discs to heat efficiently, average body perspiration will not affect the HeatWrap’s performance.

  • We don’t recommend the use of ThermaCare® for anyone, including children, who may not be able to remove the HeatWrap unassisted when feeling discomfort.

  • We don't have any data on the effect of using ThermaCare® while taking these medications. While we do not expect you to experience problems, if you are concerned about using heat products, please talk with your doctor and/or pharmacist. They will be able to advise you on your specific situation and determine whether ThermaCare® is right for you. As stated on the label, you should ask your doctor before use if you have poor circulation.

  • Oral pain medications have to be ingested and provide relief by working through the bloodstream. ThermaCare® provides pain relief by working directly at the site of the pain, relaxing the muscle and increasing local blood flow.

  • Heat may aggravate the injury if used on areas of swelling or bruising. Physicians and pharmacists generally recommend using ice periodically in the first 24–48 hours for injuries that can cause bruising or swelling. However, after 48 hours, heat such as that provided by ThermaCare® has been found to effectively provide pain relief. Consult your doctor or pharmacist for more information.

  • We don’t expect you to experience problems. However, because infant skin is delicate, we suggest you take care not to lay the baby directly on the HeatWrap. But if you are concerned about using heat products while nursing, please talk with your doctor.

  • No. Don’t use ThermaCare® on an area of the skin where other topical medicines (like topical antibiotics, pain relieving creams, hydrocortisone creams or poison ivy creams) have been applied within the past 24 hours because it may cause injury to the skin or may alter the effect of the topical medication.

  • These are the same products. We changed the name from ThermaCare® Muscle & Joint to ThermaCare® Muscle Therapy.

  • The changes were made to make the wrap more comfortable and secure to wear.

  • No, the printing will not come off on your skin. Note that the printing on ThermaCare® HeatWraps is on the clothing side of the wrap, so it should not come into contact with your skin when used as directed.

  • No, the printing will not come off on your clothes.

  • The fabric and stretch materials were change to improve comfort and security during wear.

  • The ingredients in the heat cells have not changed.

  • The new material has improved stretch.

Cold Therapy