a few years ago my mare got a super itchy neck. Per the fabulous minds of COTH we treated with ivermectin once a week. She got better but was never GOOD. Never saw exits or anything like that. She itches her tail and her neck quite a bit still so we thought maybe not NTW after all. She’s on a regular deworming program but pyrantel was not part of it last year. I gave her a tube almost 2 weeks ago. She is now having uveitis…the vet just left and found no scratch. I also noticed a hole at the top of her tail a few days ago I thought was a cut from rubbing but realize now that that looks like an exit. She has two large lumps on her neck we saw today as well I’m wondering now if it’s going to be an exit hole soon. I honestly didn’t even think about the threadworms causing uveitis and that the hole I found by her tail was an exit until after the vet left. Of course now it all looks so obvious I’m smacking my head. She’s been much itchier than normal this last week, even sitting on the ground like a dog and dragging herself around. SO I REALLY think her uveitis (first time ever) is from NTW and the deworming. Agree? Disagree? If so, how do I treat her without causing more eye damage? What is the exact protocol both short and long term? She got a shot of banamine today and steroid ointment. She’s a cresty pony so we aren’t doing dex injections. Any advice would be very helpful since I feel like this solidifies what we have suspected that she really does have NTW. For some reason they are reacting hard to the Pyrantel, perhaps because she hasn’t had it in awhile? I didn’t even know that they could affect the tail but looking at it now…that is an exit hole for sure. Ugh! HELP! I don’t want to hurt her eyes but need to get these things under control! She’s soooooo itchy all the time!
Bumping this back up to see if anyone has any thoughts on this.
Kegger, my mare has had a few uveitis flareups this year. Each one controlled right away with treatment. She is kind of a sensitive allergy/headshaker girl.
I just wonder if this incredibly humid, wet summer we have had has anything to do with it.
Maybe someone will have some ideas for you.
Absolutely juvenile NTWs can get into the eye and cause uveitis.
http://thehorsesback.com/neck-threadworms/
This cheering sentence from Scott and Miller’s Equine Dermatology sums it up: “O. cervicalis microfilariae may also invade ocular tissues, where they may be associated with keratitis, uveitis, peripapillary choroidal sclerosis, and vitiligo of the bulbar conjunctiva of the lateral limbus.”
For horses who do end up with worming-related uveitis, the typical protocol afaik is to treat with banamine preventively - dose X amount of time before and after the deworming, with X needing to be a discussion with your vet. But it is defintely useful in general, it’s just whether it’s useful specifically for your horse (but probably will be).
Thank you! Her uveitis is seemingly gone (still treating just in case.). My vet hasn’t done a NTW or deworming protocol to get this under control, so I may have to haul 4 hours to the hospital for a consult. They won’t do a distance consult with my vet since the eyes are involved, understandably. Just wondering if I should deworm more frequently to endure no load gets high enough to cause a dieoff in her eye again? And I’ll try banamine before and after deworming. Any advice would be very welcome, otherwise it’s a 4 hour drive each way to get a deworming protocol.
Caveat - see my tagline LOL
That said, there are some people who find they have to do every 2 weeks ivermectin for 3-4-5-6 times to get and keep their horse comfortable for the Summer. That protocol theoretically keeps killing the juveniles as they develop, without allowing them to get to large enough, problematic numbers.
And they learn when symptoms start appearing each year, and start deworming just before then.
The trouble is, the adults live 15 or so years, so depending on how old the horse is, how many adults were allowed to develop, this could be a problem for some horses for many years 
