leg sweats

Sweating your horse’s legs!


What is a leg sweat with Furazone? And will Furazone give me or my horse cancer?

  • Leg sweats are used to help injured legs, as the sweating compound will help reduce inflammation. Sweats also bring added heat to an area. If you have a horse with a suspected leg injury, consult your Veterinarian.


  • There are dozens and dozens of possible injuries that your horse could have, and each one with a different protocol. Sweats are also best used on older injuries, as the heat that’s created can create more problems with fresh injuries.


  • Your Veterinarian will be able to give you a detailed plan of action that involves both icing and sweating if necessary. It’s usual for a new injury to receive cold therapy, such as icing, initially before switching to a Fura-zone sweat or an ice and sweat combination days or weeks after the initial injury. Your Veterinarian can give you a specific plan for your horse’s condition.


ice boots from knee to hoof

Some horses benefit from both cold (ice) and heat (sweat) therapy. Learn when to use each type here.


How to apply a leg sweat to your horse:


  • The leg must be clean and dry! This is critical, especially if your sweat contains any amount of DMSO. DMSO is wonderfully horrible and must be used with extreme caution. Read more about DMSO here! If you are icing and sweating a leg, the ice is typically done first, then the leg needs to dry, and then you can use a sweat.


  • Check for the smallest of scrapes and irritations. Sweats can be irritating, especially so if there’s a wound on your horse’s skin. If your horse has a furry leg, it’s a good idea to clip it so you can examine the leg better and also give the sweat a better chance to work effectively.


furazone container that is half full

It’s neon and it stains!


  • Use gloves when applying a sweat. Most concoctions will stain! And speaking of concoctions, it’s always best to have your veterinarian provide you with a sweat that he has mixed, or given you the name of to pick up at the tack shop. Nitrofurazone is a common horse leg sweat, and its yellow color will stain your hands and your horse.


  • You will paint the sweat solution onto your horse’s leg, a thin layer will be fine. If you goop it on, it will escape out of your wrap! You will typically only want to use the sweat on the lower leg, under wraps.


  • Cover the sweat solution with a layer of plastic wrap to seal in the sweat. This serves to seal in the heat, and also to protect your quilt from the staining potential of the sweat solution.



  • Plan on using a leg sweat for no more than 12 hours, unless your Veterinarian has another plan. You will also want to find out how frequently to apply a sweat. Every night, every other night, weekly?

horse with one yellow standing wrap

Use quilts to cover the saran wrap, which is holding in the heat of the sweat and preventing everything in the area from becoming stained.


  • Remove the bandage and plastic wrap after the prescribed time, and wash the leg. You can usually rinse thoroughly, but you may need to add a tiny amount of mild shampoo. You will also want to use gloves for this process. This is the perfect time to inspect the leg for irritations, worsening inflammation, tenderness, etc. If you have any worries, call your veterinarian!


The actual, real information about Fura-zone! The active ingredient in Fura-zone is nitrofurazone.


  • There are a ton of blog floating saying things like “Fura-zone will give you breast cancer”, “Fura-zone causes cancer” and even more. I did a deep dive and I did find some illuminating things that can help temper the fact from the fiction.


  • Many, many years ago, Fura-zone was given to rodents, and some of those rodents developed reproductive cancers. It was FED to them, not applied topically. Here’s the original study.


  • In the early 1990’s these compounds were banned for systemic use in food production animals. At that time, it was believed that topical use was still ok. Sometime about 2002, nitrofurazones were banned for use in food animals as there was some evidence after topical use in a cow’s eye, nitrofurazone components ended up in milk and some organs. More on that here.


Which brings us to today. Carcinogens are classified into several groups:


  • Group 1: Carcinogenic to humans.
  • Group 2A: Probably carcinogenic to humans.
  • Group 2B: Possibly carcinogenic to humans.
  • Group 3: Unclassifiable as to carcinogenicity in humans.
  • Group 4: Probably not carcinogenic to humans



  • I found some information on the National Library of Medicine’s database stating nitrofurazone is a Group 3 – unclassifiable. “There is inadequate evidence for the carcinogenicity of nitrofural in humans. There is limited evidence for the carcinogenicity of nitrofural in experimental animals.”


  • Here’s what else I learned. Alcohol is a Group 1 carcinogen. Yes, my beloved WINE!


  • In summary – Alcohol CAN give you cancer. Furazone is not on the list. I TOTALLY understand if you want nothing to do with Furazone. Maybe in several years, there will be more research into this very topic. Until then, let’s stop spreading these rumors that seem to be based, very loosely, on past animal studies, that have left out some important distinctions.


So now we are back to leg sweats. In summary – you can use Fura-zone to sweat your horse’s legs. You can also skip it, your vet may have another formula to try.