Penicillin regimen

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Mar 7, 2015
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Hi Everyone,
For those of you who have had to give your bunnies penicillin injections, how often and for how long did you have to give them? Due to lack of support from my current vet and the difficulty getting appts with real experienced exotics vets around me, I am looking for information on the length and frequency of the treatment. The current dose is .25mL for a 1.8 kg bunny. Several years ago I know it was prescribed three times a week, but I feel like it was for about 3 months. There is no abscess, it's what I'm assuming to be a tooth root infection since my bunny has frequent molar trims and has had a tooth root infection before that behaved just like this. I wasn't able to get head X-rays, which would have been helpful.
Thanks in advance for any help!
This study linked below, is the dosage and frequency, that I'm familiar with. It's the protocol I'd want to follow when treating abscesses with pen g procaine/benzathine injections. Every 2-3 days, for at least a month, though longer may be needed depending on the severity of the infection. At least 2 weeks past all infection being cleared up. This is the long acting procaine/benzathine. If you only have the pen g procaine, that has to be injected daily.

The main precaution with giving penicillin injections is making absolutely sure that any leakage that gets on the fur, is very thoroughly cleaned off, particularly if it's in a spot your rabbit can reach with it's mouth. If a rabbit were to groom it off and ingest it, it could lead to fatal enterotoxemia.

For difficult infections and abscesses, I opted for azithromycin over pen g, as it acts quickly and is a shorter course, when the bacteria is sensitive to it that is. Plus it's given orally, which I prefer. But it is prescription. Only negative is some rabbits are sensitive to it and can have severe digestive upset, which if it happens then the antibiotic has to be stopped, and hopefully doesn't continue to cause a worsening of condition. My rabbits only experienced mild stomach cramping, that cleared up after a couple hours and they were back to normal.
JBun knows where its at so I'll only add my own experience with penicillin shots for tooth abscesses. For me, it was several years ago but I believe in my case it was a shot a day for two weeks. I don't remember the dose. What I DO remember is how hard it was to hold a doesn't-want-to-be-jabbed rabbit safely steady while also trying to pull up their scruff fur enough to get the needle in deeply enough and long enough to make sure its actually getting past their skin and into their system. It's not a one person job though that was how I had to do it.

And yes, one night I did think I'd injected it but I hadn't punched it through enough and it only got on her fur, which she licked off. It took less than two hours for her stomach to start to swell up and by the time I got her to the vet that same day she was visibly swollen and very uncomfortable. The vet and the techs were amazing and saved her life but I had to leave her in the hospital with them for over a week before I could bring her safely home. The injections, I was told, work faster and stronger than oral despite the risk but I will take the longer route and never again do injections. It was far too hard for me to do alone and the results of messing it up were almost disastrous (and uber expensive).

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