Hives after rain

[Debbie]

My TB geldings are on a neighbor’s pasture. Since I moved them in April, they have developed hives after every rain. They have them from head to tail and they generally disappear within 24 hours. Has anyone else experienced this? I spoke with my vet about it and he suggested treatments, but I’d really like to prevent the outbreaks. I’m guessing they are eating something that is triggering the hives, but can’t figure out what it might be.

It’s a mixed grass field with some woods. I haven’t noticed any odd plants, but I must be missing something.

[Texarkana]

I have no idea of the cause or a solution, but I’ve had several TBs with this issue!

[Flash44]

Flax seed will help.

[Debbie]

They each get a cup of flax seed daily.

[Clair2014]

I have a horse that has done this from May - September every year since I’ve moved to my farm (9 years ago). I have no idea what causes it and the vets all look at me like I’m crazy when I ask them about it but the horse consistently gets hives every time it rains.

[Texarkana]

Clair, your vets think you’re crazy, too? And here I thought I had the market cornered. :lol:

It’s been hit or miss with my horses when it happens, but it definitely has been a “warm month” thing. It also seems to be less of an issue with better nutrition. I had a more serious problems with it when my horses were boarded at places where they weren’t getting quite enough forage and a good bit of mediocre quality feed. With that said, it just happened to one of my thoroughbred mares about a month ago, so nutrition must not be the only contributing factor.

If they are really itchy or uncomfortable, I’ll treat the hives topically or with an antihistamine… but otherwise the hives go away in about a day on their own and I’ve stopped worrying about it.

[Schatzi09]

I’ve had the same issue but my horses’ hives turn into a rain rot type thing where the areas covered by the hives then get crusty lumps and the hair comes out. Most of the hairless areas are over the back and croup and not as much on the neck or shoulders. It looks terrible and my vets are stumped! I’ve noticed that most of my TB or Trakehner horses get it the worst but my 32 yr old QH is getting worse as he ages. I have found that spraying the horses with straight vinegar before the hives come up helps keep them at bay. You need to catch them after it rains and before their coats dry for it to help.

[Debbie]

The one horse has gotten them after every rain, the other had stopped getting them, but then started back last week and it has progressed into rain rot. The only change in nutrition was that I added mineral supplements.

I’ll try the vinegar treatment if I can get to them before they dry. It’s just really frustrating not to be able to pinpoint a cause, but good to know I’m not alone in dealing with it.

[csaper58]

This usually turn into rain rot where I live.

[VTMorgan06]

My mare with bad allergies would get covered with hives after being rained on. I’ve done allergy testing to know that she has quite a bit of pollen, grass and weed allergies, so the pollen and particles settle on her and stick when she is wet and cause a contact dermatitis reaction. She has done well on hydroxyzine and a fly sheet to keep prevent the contact dermatitis.

[Clair2014]

[QUOTE=VTMorgan06;8288603]
My mare with bad allergies would get covered with hives after being rained on. I’ve done allergy testing to know that she has quite a bit of pollen, grass and weed allergies, so the pollen and particles settle on her and stick when she is wet and cause a contact dermatitis reaction. She has done well on hydroxyzine and a fly sheet to keep prevent the contact dermatitis.[/QUOTE]

Interesting. You are the second person I’ve heard give this explanation for hives after rain. It makes a lot of sense.

On a different note, my horse’s hives never turn into rain rot.

[riverrunak]

My horse does this and some did turn into rain rot. Just so happened that my vet was out for an unrelated issue a few weeks ago during a breakout and she gave me some dex to give him when they get really bad. Dex, microtek and a fly sheet has helped a lot. As he also gets them in spots when there is no rain from laying in the wet grass at night.

[Texarkana]

VTmorgan06- that seems logical.

I had one horse whose hives used to turn into rain rot, but the other horses with the issue never developed rain rot.

shrugs

A vinegar bath is usually my go-to topical treatment for hives. If the horse seems uncomfortable, I give an antihistamine or corticosteroid… but that’s rare. The vinegar might be part of the reason most of mine have never developed rain rot from the hives.

[beowulf]

After rain, the bugs come out. Specifically bitey ones. Could be no-see-ums and midges.

I had one that did this too. Thought maybe it was toxic/acid rain (not sure what the acidity is here but some horses can be really sensitive to certain acids) until I watched a swarm of bugs fall upon him after a summer shower!

[One_Two_Three]

Following this! Having to deal with my second outbreak of hives with my newer horse. Both instances coinside with rain. Who knows whether it’s the pollen sticking, rain rot forming, or bugs swarming afterwards…but I’m going to bathe my guy up good tonight and do a vinegar rinse, leaving vinegar onhand to spray before and after turnout and hope that helps while I decide whether a fly sheet will help or hinder. I say hinder because I don’t think a sheet on in the rain is a good thing for a rain rot type issue… Holding in all that wet and gunk till a.m.

It’s a terrible time of year to own a thin skinned sensitive TB in Florida in summer!!!

[One_Two_Three]

Well, no one else has responded since I posted on here, but I came back to say, that a few days after the hives on my TB cleared up, he now has that funky fungusy type gunk on his neck and chest where the hives were! HOW WEIRD. Have tried spraying with vinegar, but I’m thinking maybe I was too late on that and will now be treating fungus on the neck and chest for a while…

[Limerick]

Apparently, our TB used to have skin issues after rain. His former owner put him on MagRestore and issues went away. I have kept him on Mag Restore and his skin is healthy. I know Mag Restore does not state it is for this reason but old owner felt there was a correlation.

I also have to promote Lucky Braids shampoo and Lucky Braids salve for sensitive skin issues. They are great products!!