medroxyprogesterone acetate dosing

[IPEsq]

We started my gelding on compounded medroxyprogesterone acetate this summer to see if it would help with some of his aggressive behaviors. He has residual behavioral issues from all of his past physical problems, mostly directed at me. While that has toned down with very consistent work (no more rearing or charging), he can still be a bit aggressive towards me as well as studdish being ridden around other horses, including being obsessed over certain horses’ manure, inability to focus when those horses are around, difficulty passing other horses or sharing the arena generally. For the latter issues, the drug seems to be really helping him a lot. Trying to push mom’s buttons… hit or miss

A mare that I help with is also on it because for whatever reason it works much better for her heats than Regumate (I know that’s not supposed to happen, but it’s a very big difference for her). I have to administer the shots to her from time to time. I am using the same vet for my gelding. Both are tall 17h+ WBs, though my horse is certainly heavier.

I have noticed that the vet has prescribed a dose for my gelding that is 2x what the mare gets. Both get 10ml injections every 2 weeks, but the mare gets a 100mg/ml solution and gelding gets 200mg/ml solution. This is kind of a pain in the rear for me because the 200mg/ml is harder to inject, and I nearly exploded the last dose from the bottle onto the floor, despite shaking well each time–perhaps it was just a bad syringe, because I tried with 2 different needles, but that was bottle #1 so I can’t say for sure.

I’ve read on here usually over in the h/j threads a lot of different doses. If anything my horse is even less motivated to work than usual, so I wonder if he could get by with a lower dose to still treat the aggression/studdishness. But I wanted to take an informal poll here before discussing with my vet, who I’m sure knows what he’s doing ;).

[Helicon]

My 17H gelding with stallion behavior was prescribed 7 ml of the 200mg/ml every three weeks. It seems to inject fine. I don’t use it consistently but rearing episodes do seem to coincide with when he has been off it.

I have a mare with stallion behavior I have been curious to try it on. i have not gotten a prescription yet though.

[mroades]

I actually had a bad compounded bottle that was hard to pull and inject. They took it back and replaced it. I have not had any more difficulty with 200mg/ml than the 100 other than that one bottle. That seems like a hefty dose but he is a hefty boy!!!

[limptoad]

What gauge needle are you using? I use a 20g typically. I’ve had owners mistakenly grab a 22 thinking it was a wider needle than the 20, and I don’t like using those, but I have in a pinch. 18 or 20g.

We’ve had geldings on that dose, and we’ve had them on much less. For the really studdy ones, it’s been very helpful to have them on the higher dose, get their ground manners to an immaculate place before backing the dose down.

[IPEsq]

I use 20g, same as I use for Adequan. 4 of the 5 doses in the bottle injected fine, so I wasn’t sure if I hadn’t shaken well enough, if it was just an issue with something about the last dose in the bottle, or if I had a bad syringe or what. I didn’t have any particular difficulty pulling it into the syringe…just getting it out especially for that one shot. He managed a crowded schooling area last weekend fine after losing some of the medication when I pulled out to change needles and the pressure from the failed initial injection attempt sent a little bit of it flying, so I started to wonder if he needed all 10cc.

[EmilyM]

@IPEsq

We started my gelding on compounded medroxyprogesterone acetate this summer to see if it would help with some of his aggressive behaviors. He has residual behavioral issues from all of his past physical problems, mostly directed at me. While that has toned down with very consistent work (no more rearing or charging), he can still be a bit aggressive towards me as well as studdish being ridden around other horses, including being obsessed over certain horses’ manure, inability to focus when those horses are around, difficulty passing other horses or sharing the arena generally. For the latter issues, the drug seems to be really helping him a lot. Trying to push mom’s buttons… hit or miss

A mare that I help with is also on it because for whatever reason it works much better for her heats than Regumate (I know that’s not supposed to happen, but it’s a very big difference for her). I have to administer the shots to her from time to time. I am using the same vet for my gelding. Both are tall 17h+ WBs, though my horse is certainly heavier.

I have noticed that the vet has prescribed a dose for my gelding that is 2x what the mare gets. Both get 10ml injections every 2 weeks, but the mare gets a 100mg/ml solution and gelding gets 200mg/ml solution. This is kind of a pain in the rear for me because the 200mg/ml is harder to inject, and I nearly exploded the last dose from the bottle onto the floor, despite shaking well each time–perhaps it was just a bad syringe, because I tried with 2 different needles, but that was bottle #1 so I can’t say for sure.

I’ve read on here usually over in the h/j threads a lot of different doses. If anything my horse is even less motivated to work than usual, so I wonder if he could get by with a lower dose to still treat the aggression/studdishness. But I wanted to take an informal poll here before discussing with my vet, who I’m sure knows what he’s doing ;).

i use 200mg/ml - 5 cc dose, but one of mine needs it every other week or his ADD is so severe he will end up having to pull up at jumps because he won’t look. it’s strange. he came with that recipe. I know some people give 10, but I think the 5cc dose more frequently has worked better for my horses that need it (i have 2 on it). I kind of hate that i have to give it because I don’t think we understand the long term impact it has on health, but one of mine will rear or have temper tantrums as a regular activity with me on him if i don’t.

[IPEsq]

@EmilyM

i use 200mg/ml - 5 cc dose, but one of mine needs it every other week or his ADD is so severe he will end up having to pull up at jumps because he won’t look. it’s strange. he came with that recipe. I know some people give 10, but I think the 5cc dose more frequently has worked better for my horses that need it (i have 2 on it). I kind of hate that i have to give it because I don’t think we understand the long term impact it has on health, but one of mine will rear or have temper tantrums as a regular activity with me on him if i don’t.

Mine was prescribed every other week with a 4 week loading dose of 1x a week. So, he seems to be getting a lot! But he is a really large guy. I am hoping that it will help us get a little farther along with the training but that he won’t need it or not so much long term. He never had problems with other horses in the ring as a 4-5 year old, but perhaps it was just the horses where we were at the time, since it’s not every horse at the current barn (and in fact quite a small percentage of the overall population). He did tend to have major freak outs in the show schooling areas though, and I think it helps him feel like he doesn’t have to be keeping track of everybody else all the time so he can focus on himself.

[EmilyM]

@IPEsq

Mine was prescribed every other week with a 4 week loading dose of 1x a week. So, he seems to be getting a lot! But he is a really large guy. I am hoping that it will help us get a little farther along with the training but that he won’t need it or not so much long term. He never had problems with other horses in the ring as a 4-5 year old, but perhaps it was just the horses where we were at the time, since it’s not every horse at the current barn (and in fact quite a small percentage of the overall population). He did tend to have major freak outs in the show schooling areas though, and I think it helps him feel like he doesn’t have to be keeping track of everybody else all the time so he can focus on himself.

you may find you can go to a lower dose eventually or taper. One of the two I give it to is 17.2h and prob 1500-1600 pounds. very big. it still works. i do think each horse is different, however in terms of their reaction to the MPA. I administer mine in the chest, because it can cause neck soreness and in fact the big guy does get a swelling from it. Sigh.