When you have swelling, inflammation, or pain, your doctor may recommend using a cold compress. While washcloths or ice cubes in a bag are one option, they're messy and inconvenient. Instant cold packs are a cleaner, simpler alternative. Find out more about what they are, how they work, and the best uses for cold packs.
What Cold Packs Are Made Of
Standard cold packs can be made of water or a non-toxic, slow-flowing refrigerant gel, such as hydroxyethyl cellulose. Sometimes, plastic beads filled with gel are used in the cold packs. The ice or gel is contained within a waterproof bag or envelope.
Instant cold packs are made up of two bags—one filled with water that is located inside a bag filled with a chemical, most often ammonium nitrate or urea. Squeezing the pack releases the water and dissolves the solid chemical, which then results in an endothermic reaction, instantly lowering the temperature of the package.
How to Use a Cold Pack
To use a cold pack, apply it to the sore area for 10 minutes every hour for the first three days after the injury happened, or the pain occurred. Always place a layer of cloth between your skin and the cold pack. This prevents frostbite. Starting on day four, apply cold packs to the affected area three times per day for 15 to 20 minutes each time. You should also apply the pack after activity or exercise.
How Long Gel Ice Packs Last
Most gel packs have a lifetime of 18 to 24 months. The instant packs can sit on the shelf for about the same length of time before you need to activate them. Once activated, they stay cold for two to four hours.
What Instant Ice Packs Are Good For
Instant cold packs are good for relieving pain and soreness from arthritis and injuries. They're also effective for general musculoskeletal pain, swelling and inflammation.
They are also a convenient means for treating sports injuries or applying first aid, especially in remote areas where ice isn’t immediately available.
Reusable Ice Packs
Some gel cold packs are reusable and can be used between 30 and 50 times before they lose efficacy. The chemical instant cold packs that use ammonium nitrate, calcium ammonium nitrate, or urea are not reusable. Once you activate the pack, it will stay cold for a few hours, but it will not be effective again if you try to freeze and reuse it. The chemical-based cold packs are best for travel and places where no freezer is accessible.