Separate Penicillin Counting

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Sparda29

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So yeah, we count penicillin in a different tray than we count the other drugs in because of patients with allergies to penicillin (usually is allergy to the beta-lactam compound).

Why don't we also separate the penicillinase resistant, aminopenicillins, antipseudomonal penicillins, beta-lactamase inhibitor compounds, and cephalosporins? Don't these also have cross-sensitivities?
 
you're looking into it too much...

relax...think about the hiring freeze crisis instead
 
I bet you are a supporter of banning peanuts on airplanes...

Nope, I actually got suspended in high school for a peanut incident. Apparently, the teacher was allergic to peanuts, and I was one of those people who sold candy. I had a box of Reeses, which I sold like 20 of before class, and all of them started opening up the packages in class and began to eat them, teacher claimed she was getting an allergic reaction just by smelling the peanut.
 
So yeah, we count penicillin in a different tray than we count the other drugs in because of patients with allergies to penicillin (usually is allergy to the beta-lactam compound).

Why don't we also separate the penicillinase resistant, aminopenicillins, antipseudomonal penicillins, beta-lactamase inhibitor compounds, and cephalosporins? Don't these also have cross-sensitivities?

I can also name a bunch of classes of drugs.
 
So yeah, we count penicillin in a different tray than we count the other drugs in because of patients with allergies to penicillin (usually is allergy to the beta-lactam compound).

Why don't we also separate the penicillinase resistant, aminopenicillins, antipseudomonal penicillins, beta-lactamase inhibitor compounds, and cephalosporins? Don't these also have cross-sensitivities?

Think about it. Doesn't that seem a bit impractical to you? Most pharmacies don't separate them at all, although I know of a few that separate Bactrim. As long as you keep your counting trays clean and pay attention to pt allergies it shouldn't be an issue.
 
Think about it. Doesn't that seem a bit impractical to you? Most pharmacies don't separate them at all, although I know of a few that separate Bactrim. As long as you keep your counting trays clean and pay attention to pt allergies it shouldn't be an issue.

I meant, instead of having all separate counting trays, why not just use the penicillin tray to count out those classes?
 
well, if we start seperating will will have way to many trays. A penn tray, a sulfa tray, an NSAID tray, macrolide tray, quinolone tray, opiate tray, and an everything else tray. so I could go on, but it's impractical. Just wipe them clean once in a while and move on
 
So yeah, we count penicillin in a different tray than we count the other drugs in because of patients with allergies to penicillin (usually is allergy to the beta-lactam compound).

Why don't we also separate the penicillinase resistant, aminopenicillins, antipseudomonal penicillins, beta-lactamase inhibitor compounds, and cephalosporins? Don't these also have cross-sensitivities?

Also, most of the drugs with cross sensitivities to PCNs are in capsules formulation. A500, most cephasporins, etc.

Then there is the matter of the structure. As you will learn in the future, most cross sensitivity reactions between PCN and Cephasporin is based on how closely the Cephasporin stucture relates to the PCN compound. The majority of the drugs that you mentioned has no chemical compound that looks remotely like a PCN and would not activate antigens to mediate a reaction. (That is a big reason why there is a 10 percent cross sensitivity between Cephasporins and PCN).
 
The majority of the drugs that you mentioned has no chemical compound that looks remotely like a PCN and would not activate antigens to mediate a reaction. (That is a big reason why there is a 10 percent cross sensitivity between Cephasporins and PCN).

I thought most of them he listed looked very similar to PCN. With 10-15% cross sens. I wouldn't give a true PCN allergic pt a cephalosporin.
 
I thought most of them he listed looked very similar to PCN. With 10-15% cross sens. I wouldn't give a true PCN allergic pt a cephalosporin.

Nope, if you still have your cephasporin med chem structures, you'll be surprised how different they look from PCN.

It's a clinical decision. That is why we are here. If the benefits outweights the risk, then give it. We are not robots. . .

For example, somebody with a true PCN allergy (including anaphylatic shocks and all) would still get PCN for syphillis. Sure we de-sensitize them first but that is still dangerous in itself.
 
cephalexin

220px-Cefalexin.svg.png


PCN

180px-Penicillin-core.png


ampicillin

220px-Ampicillin_structure.svg.png


dicloxacillin

220px-Dicloxacillin.svg.png



They all look pretty similar to me. The desensitization thing for neurosyphilis is a whole different story, I'm talking about giving a pcn allergic pt a cephalosporin when there are other alternatives.
 
<p>
For example, somebody with a true PCN allergy (including anaphylatic shocks and all) would still get PCN for syphillis. Sure we de-sensitize them first but that is still dangerous in itself.
</p>
<p>&nbsp;</p>
<p>Depends on what stage they're in. You'd only have to desensitize in late-latency/neuro.</p>
<p>&nbsp;</p>
<p>The fact that ceftriaxone is one of the alternatives gets back to the earlier discussion, though...</p>
 
They've pretty much disproven the myth that the cephalosporin/pcn cross sensitivity is 5-10%. It's more like < 1%. And that's only incidence of rash/pruritis. The vast majority of the time when people think they are having an allergy to something, it's just a run-of-the-mill side effect. But know this - the rate of true anaphylaxis with cephalosporins in relation to those with and without known pcn sensitivity is exactly the same.

Here's a good article.
 
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They've pretty much disproven the myth that the cephalosporin/pcn cross sensitivity is 5-10%. It's more like < 1%. And that's only incidence of rash/pruritis. The vast majority of the time when people think they are having an allergy to something, it's just a run-of-the-mill side effect. But know this - the rate of true anaphylaxis with cephalosporins in relation to those with and without known pcn sensitivity is exactly the same.

Here's a good article.

Nice.

"Administration of cephalothin, cephalexin,
cefadroxil, and cefazolin in penicillin allergic
patients is associated with a
significant increase in the rate of allergic
reactions; whereas administration of
cefprozil, cefuroxime, cefpodoxime, ceftazidime,
and ceftriaxone is not."
 
Sorry, I made a typo. I was thinking of and meant chemical side chains.

http://en.wikipedia.org/wiki/File:Cephalosporins_Generation1.svg

A true allergic reaction requires stimulation of the immune system. It also requires a few days before there is an allergic reaction as it takes time for antigen/antibody production. I was thinking of the chemical structure because usually the reaction depends on protein/tissue bindings----> hence predictablity based on side chains.
 
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In the long history of Pharmacy has there been a report that shows or even implies that cross contamination of a non penicillin drug with penicillin powder from a counting tray has been the cause of an allergic reaction?

I think this is one of those theoretical things that makes sense when you think about it, but in reality never happens......
 
That's what I was wondering...I worked for 1 boss who had a separate pen tray, and in the 20 years since, nobody else has and as far as I know, nobody's died.

If you have a severe penicillin allergy, can you work as a pharmacist? What of the pill dust?
 
That's what I was wondering...I worked for 1 boss who had a separate pen tray, and in the 20 years since, nobody else has and as far as I know, nobody's died.

If you have a severe penicillin allergy, can you work as a pharmacist? What of the pill dust?

Just get your techs to count the penicillin and have them hold it when you verify it.
 
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