Short course injectable antibiotic usage?

RE: Short course injectable antibiotic usage?

David Mills — Wed, 06 Nov 2024 16:07:00 GMT

[quote userid="5012" url="~/f/clinical-questions/31069/short-course-injectable-antibiotic-usage/245940#245940"]

This is the bit I don't fully understand.

We were taught that if a course of antibiotics was too short, and not all the targeted bacterial were killed, then we may have a clinical but not a bacteriological cure, but those not killed will more likely be resistant. Hit longer and hit harder we were told.

[/quote]

As I understand it there are generally three types of resistance - inherent (or previously induced), dose-dependent and inducible.

Inherent will be resistant regardless of length or strength of course. These can be the same bacteria as ones that are sensitive, or they can be naturally resistant to the mode of action of the antibacterial.

Dose dependent are ones that will be killed if the dose or sometimes the length of the course are sufficent to reach tissue levels that overwhelm any resistance. Ears and bladders are classic examples.

Inducible are those bacteria that become resistant because the dose or sometimes length is insufficient to produce tissue levels high enough meaning the bacteria become resistant (either themselves or transfer from other bacteria).

Antimicrobials work by killing a certain % of bacteria, leaving the body to clear the rest. A short course of the right dose will therefore reduce bacterial load sufficiently to ensure the body can sort out the rest whilst reducing resistance selection pressure. Used prophylactically, it is similar to scrubbing a dog before surgery - looking to reduce bacteria to below a certain point to minimise risk of infection related to the surgery.

It doesn't mean they aren't still overused however.

RE: Short course injectable antibiotic usage?

Evelyn Barbour-Hill — Wed, 06 Nov 2024 15:08:35 GMT

[quote userid="5012" url="~/f/clinical-questions/31069/short-course-injectable-antibiotic-usage/245940#245940"]

Evelyn Barbour-Hill said:
It seems patently obvious that if you really need to give some antibiotic (and are you sure?) then the short course – i.e. the single injection – exerts a lot less pressure to induce resistance.

This is the bit I don't fully understand.

[/quote]

Yes, that's more or less what we were told. Dutifully that's what I did for a good few years. I never really understood it.

We were also taught that every surgical operation needed a dollop of Propen, that tetracycline was more effective if given intravenously, and a few other things we now know to be nonsense.

RE: Short course injectable antibiotic usage?

Clive Ansell — Wed, 06 Nov 2024 13:06:54 GMT

[quote userid="2131" url="~/f/clinical-questions/31069/short-course-injectable-antibiotic-usage/245788#245788"]It seems patently obvious that if you really need to give some antibiotic (and are you sure?) then the short course – i.e. the single injection – exerts a lot less pressure to induce resistance.[/quote]

This is the bit I don't fully understand.

RE: Short course injectable antibiotic usage?

Andrew Kent — Wed, 06 Nov 2024 09:20:51 GMT

ENOVAT is another organisation doing great work in this area, see https://www.sciencedirect.com/science/article/pii/S1090023324000406?via%3Dihub

RE: Short course injectable antibiotic usage?

Stigen — Wed, 23 Oct 2024 12:33:33 GMT

I will check it out. I did read a good BSAVA article about antimicrobial prophylaxis though; www.bsavalibrary.com/.../20412495.1118.4

RE: Short course injectable antibiotic usage?

Alasdair Hotston Moore — Wed, 23 Oct 2024 08:41:52 GMT

Have you seen the PROTECT guidelines on the BSAVA website (free to all)?

RE: Short course injectable antibiotic usage?

Stigen — Wed, 23 Oct 2024 06:53:42 GMT

Thanks , I do not routinely use them for periodontitis extractions. But in general there are some cases where I feel like there is a risk of infection and I wanna give their immune system a little "boost" by a one off injection, and want to avoid peroral administration. Sometimes also after cleaning out a cat abscess. Before we always gave a course of antibiotics for those, but these days I mostly just flush them well and give them the high dose clamoxyl, and see back after 5-6 days.

RE: Short course injectable antibiotic usage?

Evelyn Barbour-Hill — Tue, 22 Oct 2024 17:25:44 GMT

We use far too many doses of antibiotic drugs. It seems patently obvious that if you really need to give some antibiotic (and are you sure?) then the short course – i.e. the single injection – exerts a lot less pressure to induce resistance.

I won't bang on about that, but I will assure you that you do not need any antibiotic after dental extractions however much periodontitis there is.