ok i have a twenty four year old paint. last year one of our other horses bit him on his withers and the wound healed up with in about 2-3 weeks, but about three months ago he has dropped severe weight and the wound has reinfected and gotten ten times worse than the first we have given him penisulin and put fura-zone all over it and nothing has helped. its gotten so bad that about three weeks ago their were maggots covering the area. we scrapped those off and they havent came back but what has been happening is he is loosing his hair and not just in a shedding way but in a big patchy way (almost a foot in size on some) and its really starting to scare me that just nothing is helping him anymore....I NEED HELP PLEASE!! any suggestions would be greatly appreciated..
my name is kacie if you have any comments

Hey girl, first off I'd say GET a vet. Even if you don't have him out, at least give him a call. He/she will tell you exactly what is going on and what needs to be done. Good job with penicillin. He will probably need a booster antibiotic such as Tucoprimm (or Uniprimm) which is a feed-through.
Fura-Zone works, but it does have some ingredients which are not really skin friendly. I've seen problems with using it on some horses, and some not. If the wound is not healing, you more than likely need to switch medications.
Keep fly spray around the area to ward off flies which will lay eggs in the wound, and other insects. Wash and soak the area a few times a day with cool water.
If you have any horse-experienced neighbors or friends, find someone who's dealt with this and can talk to you.
And call a good horse-vet !

Good luck, hope he gets better soon and please keep us updated- I would love to hear how he comes along.

I was just reading your post. before I gt all into detail, I will just ask how it is going. As it was several months ago. Let me know and if there is still an issue maybe, I can help.
Leisa

I hope by now the vet has fixed your horses problem. Withers are prone to developing a fistula, a deep infection the body tries to wall off. Because of gravity when the wound tries to drain, it is very hard to open and keep draining. A small abcess was walled off, or even a bruise over the withers, it eventually got inflammed and needed to drain. These can become the size of basket balls and very hard to resolve. The vet will most often, in surgery, try to remove the entire abcess and put in drains. The area is treated with antibiotics topically and injectable. A culture will tell the vet the best antibiotic to use to clean up the remaining infection. By using a culture, the vet can get the antibiotic that is the best for combatting the type of bacteria found. I have found Granule-X spray, keeps the dead tissue off the area when you have a large area, or a slow healing area below the hock or knee.
These are hard to heal and the sooner you get your horse to a facility that can perform the surgery the better the outcome. Any wound high on the wither or hip, that gets infected needs to be seen by a vet to have drains put in at the lower ends of the wound to keep the wound draining.
Your horse may be playing and fall over backwards and cause a bruise that you may not be aware of. Several weeks even months later Fistula of the Withers may develop as a result. They are often very large. Early vet care is vital to a good outlook, this can be very hard to heal completely. Good Luck