Pen G dosage

I've done a search of the forum and found numerous suggestions, but can't really make heads or tails of them.

I've decided I need to give Pen G to 2 of my grown English lop does. They are not bred or nursing, and weigh approx. 10 1/2 lbs.

I've purchased small syringes with ml on them, I just need to know the dosage and how often. I plan to give it sub Q.

I had to do the math with a 5 lb bunny, and ended up giving 1/4ml once a day for 7 days.

This was for PenG at 300,000 strength, I think.

So 1/2ml would probably be the dosage you need to use.

I didn't know there was a difference in the Pen G strength. I checked the bottle and it does say 300,000 units per ml.

generally, 0.1 cc per 2 pounds body weight loading dose followed by 0.1 cc per 4 pounds body weight every other day. So a 5 pound rabbit gets 0.50 cc subcutaneous x 1 (DuraPen/ BiCillin )then 0.25cc SubQ every other day until symptoms have been resolved for at least 7 days. Infection in rabbits such as abscess, respiratory infection, or rabbit syphhilus lingers asymptomatically and needs prolonged, aggressive treatment.

I had one very beloved doe with a sinus abscess who required a 4 week course with double the recommended dosing (0.20 cc per 2 pounds loading dose then 0.1 cc per pound every other day). We also treated her with Sulmethazine at the same time because abscesses tend to have multiple bacteria species. The good news is, she is well and has stayed well. Most other rabbits would have been culled, but she is one of my original matriarchs and just an awesome rabbit. <br /><br /> -- Fri Mar 21, 2014 1:48 am -- <br /><br /> PS be sure the penicillin G product is labelled for subcutaneous use. There are 2 products for sale at feed stores, one is for intramuscular injection and the other is for subcutaneous injection. They are actually different formulas and are metabolized differently. The "bicillin" procaine penicillin for subcutaneous use has two types of penicillin G in the formula, which gives it a long half-life (therapeutic window) in the body system and is well-tolerated by small animals such as rabbits, cats and dogs. The half-life is 48 hours, hence the need for every-other-day dosing instead of daily dosing.

The bottle states it is for both subQ and IM usage.

I am treating some form of eye infection that thus far has been impervious to daily washing with water, then to daily eye ointment application, then to antibiotics in the drinking water. I am now giving an actual penicillin shot a chance to see if that will clear it up. I hate to do this, as I am actually quite allergic to penicillin myself, but short of taking them to the vet, I don't see another course of action.

Of course, this is affecting only 2 of my some 40 animals, and both are top show does entered in 2 weeks at the lop national convention. They are at least 15 feet away from each other in the barn, and none of their neighbors have it, so apparently it is not airborne.

Both does were born and raised here, so I doubt it is some type of allergen. I am really at a loss as to what it is, why they have it, or how they got it.

Hopefully it will only take a shot or two to get it cleared up. I don't like to doctor my animals, but I feel both of these does are worth the effort. I plan to give the first shot either today or tomorrow, and will continue depending on how it seems to affect the eye problem.

I have seen a number of different dosage regimens for PenG (as you can see from the ones Diamond and I posted). The first time I gave it, I had to just decide on one to go with. So that's what I've done with it.

I would not give just a shot or two. That could clear up symptoms, yet not kill the infection. It could come roaring back, tougher to treat because what wasn't killed is the more resistant bacteria. You really should continue for the whole course, to make sure to the best of your ability that you've killed the whole infection.

Do watch them, to make sure they continue eating and drinking. I actually lost a doe because she stopped eating the last couple of days of her treatment. I waited for her to get her appetite back, and she died of gut stasis. They don't have to be eating a lot, but they have to be eating. At least hay or oatmeal or something. I didn't know that they have to always have at least a little food going through their system, until this happened.

I was just calculating a Dura-Pen dosage today for a five pound rabbit, it got more complicated than I'd expected. The recommendation was "42.000 - 84.000 UI/kg, SC, IM), 4-6 repeats at intervals of 5 to 7 days" so there was math and medical interpretation involved.

The first thing is that some European numerical systems use a period instead of a comma in their numbers, so it's actually "42,000 - 84,000". Which is a rather large range, IMHO. I'm calculating for the lower end of that range, the "42,000 UI/kg".

The "UI" or "IU" (it can go either way depending on which language it's in) is "International Units" and is just a type of medical measurement. One IU is a very miniscule amount. The important part is "UI/kg" which is "International Units per Kilogram". So now we're in kilos instead of pounds.

One pound is 0.453592 kilograms. So, a five pound bunny is 2.26796 kilograms. If the bunny needs 42,000 UI per Kilogram, it would be 95,254.32 UIs for the 5 pound bunny. So how many mL is 95,254.32 UIs?

Each milliliter (mL) of Dura-Pen is 300,000 UI. So the necessary dose is about one third mL, or using math .3175 mL. (to use the math, divide the 95,254.32 by the 300,000). Considering how much leeway there is in the recommended dosage, one third would be fine, but with tiny syringes, we can get really close to the .3175 We got a one mL syringe from the feed store, it's a good thing we got several since we did bend one needle.

So, twenty bunnies got shots today. So far so good. I'm not sure if they should get six sets of shots every five days or four sets of shots spaced seven days apart?

Also need to figure out how to sterilize the hutches. That's gonna be a pain. I'm figuring a bleach bath/spray probably starting after their next round of shots.

Also need to figure out how to sterilize the hutches.

Click to expand...

What are you treating the rabbits for, Hotcatz? Sorry I can't remember, but it's hard to keep track of everything. :roll:

Hello Hotcatz. So I went in and did the math for you. The dose you would give for the 42,000 IU range would be 0.32 mL. As far as the duration of how and when you would give the shots depends on what you are trying to treat for. Like MaggieJ said "What are you treating the rabbits for, Hotcatz? Sorry I can't remember, but it's hard to keep track of everything. :roll:"

If it is an eye infection i would apply the antibiotic topically to the eye itself. That has always cleared up infections in the eye for me and you will not have to worry about it bothering your buns digestive system.

I feel like I should book mark this thread for future reference.... lol... the math Hotzcatz did .... well, lets just say I don't want to have to repeat those calculations with out guidance....lol

The formula for the that is:

Weight * Dose / concentraion= amount to be given

Meaning you take the weight of the rabbit, pounds or kilograms depending on how it is dosed, multiply by the dose, then divide by the concentration of the bottle.

To convert pounds to kilograms

wight in pounds / 2.2 = kilograms