Reserpine side effects

My boy has been on stall rest/limited hand walking for a check ligament tear since early September. We are in phase two and will have U/S #3 next week. He’s been better than I thought but not as good as I hoped. Sigh. This included reoccurrence of his old habit of stall kicking and walking sometimes proved a bit hazardous. So we put him on reserpine. It seems to have helped, however, today he developed diarrhea-which is listed as a common side effect. We are checking with the vet but should I push to Discontinue? I’m hoping Monday we’ll get clearance to start back in tack which could be a real trial without some chemical help.

My horse never got diarrhea on Reserpine - but it never quieted him either! (We kept increasing the dose until the vet wasn’t comfortable increasing any more) The instructions I got were to reduce the dose. A little floppy was okay though…

My mare had loose manure on Reserpine - not quite diarrhea though. It stopped once we weaned her off it - she was on it short term. That was really the only side effect I can remember.

Maybe ask your vet about adding Biosponge for a couple of days? It’s worked wonders for a few horses in our barn.

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Many years ago I had my vet give a horse of mine a shot of reserpine that was supposed to last 6 weeks. All it did was make him super paranoid and have terrible diarrhea for the majority of those 6 weeks. I agree that maybe trying biosponge would help? I suppose the decision to discontinue comes down to whether he poses more of a risk of re-injury without it. Diarrhea’s not the end of the world, and in most cases (if the reserpine is working otherwise) seems like it would still be a better option than the risk of re-injury.

If you’re administering the reserpine orally, you might try backing off the dose slightly.

I don’t know what form of Reserpine you used (oral vs injection), but the problem with the injectable type is it’s long lasting and horses have been known to ummm “paint the walls”. :no:
Oral daily dosing is preferred because you can play with the dosage, usually between 2.5mg - 10mg.
Do you know what your horse recieved?

With the stress of stall rest and resuming stall walking and kicking, combined with the reserpine, I would think about treating him for ulcers. Reserpine is really hard on them and, especially for ulcer-prone horses, can contribute to ulcers.

And yeah, diarrhea is a common side effect. Depending on how it was given (oral vs. injectable) you might be able to play with the dosage but IME there are usually other better alternatives like Ace, xylazine, etc., depending on the circumstances.

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My horse was on injectable reserpine and we did loading doses for about 7 days - daily or every other day smaller doses until the level of sedation we wanted was achieved and then we maintained with weekly doses for 4 months. Towards the end of the stall rest, I actually ended up dosing him almost every other day with smaller amounts as he was getting worse in his stall.

My horse did have diarrhea and was on Abler pop rocks the whole time. He also started shivering/quivering after the second to last loading dose at the beginning but never displayed that effect again. He would be a bit wobbly in the cross ties after his weekly dose.

I took him off of the reserpine after we were done with hand walking and had started tack walking. He was weirdly spooky under saddle - very noise sensitive and almost a delayed reaction to things. He graduated to a ~30 x 30 ft pen outside at the same time, which helped his sanity as well.

Mind had loose manure and got really nasty. She also started having extreme spookiness and going nuts in hand - almost like a panic attack. It took a few weeks off of it for her to return to normal.

I had mine on the oral type. I didn’t have any diarrhea issues, but I’m not sure it really kept him quiet. If it did…God help me the next time he needs to go on extended stall rest!

He had a barn buddy… he had a “stall outside”…he had a “stall plus outside”…he became unsafe to handle drugged. I turned him out with a buddy in a small paddock and “if he made it, he made it” became the mantra. When the farm hand let me know he was galloping about and sliding stop? (still on the the oral meds), I gave up and turned him out.

Lucky for me it was just a strain (fluid in the tendon sheath, but no evidence of damage to the tendon). He is NOT a candidate for rehab from a devastating injury.

I will never give it to my horses ever again. My WB was in rehab and had her on it and she got colitis. If you research it you’ll see that some horses have a much greater chance of getting colic or colitis from this drug. It was a very expensive lesson. Luckily she survived.

The cost/benefit analysis of continuing medication is really going to have to be a conversation between you and your vet. I would personally be hesitant to discontinue the reserpine if I thought it was making my horse and myself safer. You could try to treat the digestive upset to get you through the next couple of weeks, but unfortunately reserpine isn’t drug without risks.

I would encourage you to err on the side of physical safety. If you can’t make the reserpine work, please find something that does. You won’t be able to attend to your horses digestive health if you’re smeared on the side of the indoor.

Mine had diarrhea for a couple of days and that was it.