I've tried everything from 16-21, and my favored size is 20. It creates a smaller hole so that the cat's skin doesn't develop scar tissue as quickly as with a larger needle, and it's more comfortable for the cat. The speed of flow is quite adequate with a 20, particularly if you have a helper who can hold the fluid bag high above the cat during administration. If your cat is really squirmy during administration, though, you might do better with a larger gauge to increase the flow rate and make the whole process go more quickly.

I have read again and again that Terumo needles are much sharper and more easily inserted than Monoject needles. I've also read that the Ultra Thin Wall Terumos allow for the flow speed of a larger needle in a smaller gauge size, so I bought a box of 20X1" Terumos to try out. Unfortunately, I didn't specify Ultra Thin Wall on my order, so I ended up with regular wall Terumos. They were fine, but if I need to order again, I'll order 21X1" Ultra Thin Wall Terumo which should provide the same flow rate as the 20 gauge regular wall with a thinner needle.

You can always just pick up a few 20X1" needles from your vet to try out with your cat and see how (s)he responds to them before ordering a whole box.

Laurie

Thank you, Laurie! I read your post shortly after you made it, but haven't had a few minutes to sign on until now.

The place I get needles from doesn't require an RX for needles, so I ordered enough 18s to use on the next case of Ringers (also ordered through them w/RX) and ordered a few 20s to see how we like them. Then we can decide if we want to stick with 18s or go to 20s.

You're the first person who's explained the scar tissue situation, which led to a 'duh moment' as that makes sense once you think about it. I'll look around for those Terumo needles too.

Thanks again, it's much appreciated!

I just had to use a 20-gauge on a horse - viscosity penicillin. I asked the vet - "does penicillin go through a 20?" He said, "Barely." But I had to give the horse so many injections that I preferred the 20 though I had to inject slower. It seemed to be less noticeable to the horse.

Great info laurief - next time I get needles, I'll notice the brand - though I'm sure they're nothing special since I get them at a livestock/pet feed store.

vicky

I always use 20 ga on my horses. I have one mare who will try to kill me if I go any larger than that. Yes, pen. moves slowly through a 20 ga., but I'd rather survive a slower injection than end up hospitalized with a faster one. ;-)

Terumo needles are difficult to find at vets', feedstores, and pharmacies, but they can be purchased online.

Laurie

I've only used 18 gauge that I get at the vet, but the Terumos I've used are definitely sharper than the others. Next best is Monoject. I bought a few of one kind that I threw in the trash. The cat yelled when I stuck him. I told them at the vet and they looked at me like I was crazy, like a needle's a needle. I don't remember the brand, but they were individually packaged in a white and pink wrapper. Where do y'all get Ringers? I've been getting it from the vet. I pay $9 a bag, I think. My cat gets 200 ml daily.

The page linked below will help you locate inexpensive sources for all sorts of CRF supplies and meds.

Here is a link that might be useful: CRF supply sources

irislover, I get mine at valleyvet, which is listed on the page from the above link. Great service and I usually spend enough to get free shipping. Ringers is only $2.99/liter there. $9 sounds steep, but when we first started this process, my vet (who I consider to be fairly priced) charged me $30/liter! I guess they don't stock the stuff except for their own surgery needs and prefer that clients get it at the pharmacy with an RX- but those were the first trial bags to make sure it was going to work.