amoxicillin overdose?

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chloroform2009

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What is the maximum amoxicillin dosage for the standard adult for standard prophylaxis/infection? At what dosage will there be signs of toxic effects? Is 3 grams daily of amoxicillin ( such as 2 tabs q8h or 1 tab q4h ) considered unsafe?

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Ask the physician/dentist who wrote you the prescription. Or the nurse when she hands it to you. Or the pharmacist when you fill it.

No offense but that's not a helpful answer. ( by the way, I find it interesting that you replied in the order of physician>dentist>nurse>pharmacist. lol )

I'm just asking general questions. I can't find any direct literature that talks of the maximum safe dosage for the typical adult.
 
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No offense but that's not a helpful answer. ( by the way, I find it interesting that you replied in the order of physician>dentist>nurse>pharmacist. lol )

I'm just asking general questions. I can't find any direct literature that talks of the maximum safe dosage for the typical adult.

I answered in order of who would see the prescription...not qualifications.

If you're asking for general knowledge purposes, then I'll give you a helpful answer: there is a good reason why you're unable to find any literature talking about the maximum safe dosage in an adult. The answer to your question is also contingent on your definition of toxicity...come up with a definition, and you'll have your answer.
 
What is the maximum amoxicillin dosage for the standard adult for standard prophylaxis/infection?

Prophylaxis for what?

And what type of infection?

At what dosage will there be signs of toxic effects?

What kind of toxic effects?

Is 3 grams daily of amoxicillin ( such as 2 tabs q8h or 1 tab q4h ) considered unsafe?

For what use? 2 tabs of what strength? 1 tab of what strength?

Knowing how to ask questions is just as important.
 
Is 3 grams daily of amoxicillin ( such as 2 tabs q8h or 1 tab q4h ) considered unsafe?

3 grams in a single dose is fine for gonorrhea and acute, uncomplicated ano-genital infections. A study at a poison control center found that even a 250mg/kg dose wasn't associated with toxic effects. That was in a pediatric population.
 
I answered in order of who would see the prescription...not qualifications.

If you're asking for general knowledge purposes, then I'll give you a helpful answer: there is a good reason why you're unable to find any literature talking about the maximum safe dosage in an adult. The answer to your question is also contingent on your definition of toxicity...come up with a definition, and you'll have your answer.

I know there are many variables involved but I'm not speaking on behalf of a specific reason for taking amoxicil. I feel that would be too specific. And a toxic dose is toxic no matter what the reason is for taking it. By toxic, I mean severe symptoms, such as dyspnea or death.

Now, can I get a general idea of what would be a safe maximum dose for an adult, and yet isn't potentially toxic? ( assume the adult is of typical weight and is healthy )
 
3 grams in a single dose is fine for gonorrhea and acute, uncomplicated ano-genital infections. A study at a poison control center found that even a 250mg/kg dose wasn't associated with toxic effects. That was in a pediatric population.

How would a single dose of 3 g. vs multiple doses adding up to 3g. differ from each other in toxicity ?
 
I know there are many variables involved but I'm not speaking on behalf of a specific reason for taking amoxicil. I feel that would be too specific. And a toxic dose is toxic no matter what the reason is for taking it. By toxic, I mean severe symptoms, such as dyspnea or death.

Now, can I get a general idea of what would be a safe maximum dose for an adult, and yet isn't potentially toxic? ( assume the adult is of typical weight and is healthy )

If those are the toxic effects you're looking for, good luck finding anything. Amoxicillin might cause severe GI effects at high doses, but I doubt anything approaching a lethal dose can be administered to a human under normal circumstances (barring allergic effects). There was a case about a year ago of a toddler who received 9 grams of unmixed powder with nothing worse than diarrhea and some vomiting.

Basically, what I'm getting at, is that it's safe. You might reach a limit that a patient can reach on GI effects, but you'd have to force-feed them the stuff to kill them. So, by default, the safe maximum dose becomes the maximum effective and tolerated dose. I'll get my kinetics professors if you want to talk about the maximum effective dose.
 
How would a single dose of 3 g. vs multiple doses adding up to 3g. differ from each other in toxicity ?

The short half-life and rapid renal excretion in a healthy person suggests there wouldn't be a difference. The kinetics would differ, but I don't think toxicity would differ. But I don't know of a study that would confirm this.
 
The short half-life and rapid renal excretion in a healthy person suggests there wouldn't be a difference. The kinetics would differ, but I don't think toxicity would differ. But I don't know of a study that would confirm this.

Well, the AUC would be the same if it's multi-dose vs single does given nothing goes non-linear. Renal excretion might, since it's actively secreted. But the big difference would be the peak level from the single dose would be very large. so is the toxicity coming from increased exposure (AUC) or high levels (peak)
 
Guys:

Pharmacokinetics plays zero role in this come on. It's basic Bio 101..... Think what do bacteria have that we don't have.......
 
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so is the toxicity coming from increased exposure (AUC) or high levels (peak)

That's the question. I'm having a hard time finding any studies. Quite a few case reports of non-fatal overdose, but no toxicity studies. I think one reason is that, as Praziquantel86 mentioned, amoxicillin seems to have a Burj Dubai high therapeutic index.
 
That's the question. I'm having a hard time finding any studies. Quite a few case reports of non-fatal overdose, but no toxicity studies. I think one reason is that, as Praziquantel86 mentioned, amoxicillin seems to have a Burj Dubai high therapeutic index.
Wonder why that is?????

we are talking about toxicity not, chemotherapy. so the fact that bacteria have something I do not doesn't matter.

You are wrong..... Think again. Answer my question......
 
You are wrong..... Think again. Answer my question......

What are you talking about? look at the first post below

What is the maximum amoxicillin dosage for the standard adult for standard prophylaxis/infection? At what dosage will there be signs of toxic effects? Is 3 grams daily of amoxicillin ( such as 2 tabs q8h or 1 tab q4h ) considered unsafe?

If this doesn't sound like toxicology, I don't know what does. I see nothing about chemotherapy. "toxic effect", "Unsafe"!!! so I don't care what bacteria have becasue it has no role in answering teh question

I guess CVS will hire ANYONE with a license,
 
I know there are many variables involved but I'm not speaking on behalf of a specific reason for taking amoxicil. I feel that would be too specific. And a toxic dose is toxic no matter what the reason is for taking it. By toxic, I mean severe symptoms, such as dyspnea or death.

Now, can I get a general idea of what would be a safe maximum dose for an adult, and yet isn't potentially toxic? ( assume the adult is of typical weight and is healthy )

Indication means everything. Specificity means everything in infectious disease. Without either, a dose cannot be justified. Dyspnea and death would commonly result from anaphylaxis which could be from any real therapeutic dose. But if you were a student you would at least know that.

How would a single dose of 3 g. vs multiple doses adding up to 3g. differ from each other in toxicity ?

you obviously don't have any experience in the health field..... Are you soliciting advice from this forum?
 
Jesus. Humans DO NOT have cell walls. Amoxicillin disrupts the synthesis of cell walls, which are found in bacteria.

And your point? A substantial amount of toxicity in drugs results from off-target effects, especially with antibiotics. Some examples: aminoglycosides and ototoxicity, vancomycin and Red-Man syndrome, linezolid and neuropathy.

None of the above antibiotics target something found in humans, yet all are very real toxicities.

Amoxicillin is very non-toxic, but not necessarily because it doesn't effect a human target.
 
Guys:

Pharmacokinetics plays zero role in this come on. It's basic Bio 101..... Think what do bacteria have that we don't have.......

That couldnt be the farthest from the truth.
 
According to Poisondex: Gastric decontamination is recommended if the amount ingested is 15 or more times the therpeutic dose. Apparently renal failure has been reported with large doses, so I don't think the answer to the question is as simple as "we don't have cell walls".

It would be hard to ingest that much amoxicillin. 45g is a lot.
 
IS that what Old Timer is getting at?!?. We don't have cell walls so amox is non-toxic to humans. We also don't have 50S ribsomes but I'm not about to go pound chloramphenicol and ask my RBC if they have any friends left
 
while you guys are arguing a way, I think the OP is some creep soliciting health advice. this thread should be locked.
 
Listen guys, if you take enough of just about anything, it can kill you. The reason that Amoxicillin is almost non-toxic even at high doses is we don't have cell walls. What could it do to us? Unlike macrolides which may interfere with the metabolism of other drugs, or aminoglycosides which can cause ototoxicity by interfering with the mitochondrial ribosomes which appear to be more closely related to prokaryotic ribosomes than eukaryotic ribosomes, Penicillins appear to have no direct effect on eukaryotic cells. I guess pharmacokinetics could play a role if you could show some level of toxicity at all let alone some level that could be achieved even in patients with altered renal function.

Some things are simple. The reason why you get nausea vomiting diarrhea as main symptoms of even large or what you could call over-doses of penicillin are local GI effects either due to concentration or it's effect on the GI flora.

Has there been a case of morbidity and mortality due to Penicillin over dose? I don't have access to journals like most of you so I could stand to be corrected, but I don't think so....
 
IS that what Old Timer is getting at?!?. We don't have cell walls so amox is non-toxic to humans. We also don't have 50S ribsomes but I'm not about to go pound chloramphenicol and ask my RBC if they have any friends left

It appears that chloramphenicol toxicity is due to a ribosomal effect and the mechanism of this effect is the same as is noted above for aminoglycosides. The mitochondrial ribosomes appear more closely related to bacterial ribosomes and therefore you get the noted effect.

Just because we don't have 50S sub units doesn't mean somewhere we don't have ribosomes that are similar.
 
If PK doesn't play a role, why the dose is 500 TID x 7 days for a lot of indications instead of 1500 qday x 7?

Please educate me.
 
If PK doesn't play a role, why the dose is 500 TID x 7 days for a lot of indications instead of 1500 qday x 7?

Please educate me.

Toxicity and therapeutic effect are not the same.... Why is 875 BID now an approved dose?????
 
If PK doesn't play a role, why the dose is 500 TID x 7 days for a lot of indications instead of 1500 qday x 7?

Please educate me.

Actually, according to the most recent AHA guidelines, amoxicillin given at 50 mg/kg/day once daily in pharyngitis is just as efficacious as bid or tid dosing.
 
Actually, according to the most recent AHA guidelines, amoxicillin given at 50 mg/kg/day once daily in pharyngitis is just as efficacious as bid or tid dosing.

Was that a time dose or a single dose treatment? In out fictional 70KG man that's 3.5gm
 
Actually, according to the most recent AHA guidelines, amoxicillin given at 50 mg/kg/day once daily in pharyngitis is just as efficacious as bid or tid dosing.

Do they use Moxatag (Amox ER) for that? Or regular Amox?
 
Toxicity and therapeutic effect are not the same.... Why is 875 BID now an approved dose?????

I don't mean to argue with you. But I think the blood concentration of a drug is correlated with toxicity and therapeutic effect. I never said they were the same. Even if 875 bid is approved for some indication, it does not mean PK is not important for amox. As a matter of fact, the approval may be based upon the results of PK studies. If you just goolgle amox + PK, there are a whole bunch of studies out there.
 
Do they use Moxatag (Amox ER) for that? Or regular Amox?

They used regular Amoxicillin. This was based off of studies done in peds patients that demonstrated that once daily regular amox was equivalent to the bid or tid dosing.
 
I don't mean to argue with you. But I think the blood concentration of a drug is correlated with toxicity and therapeutic effect. I never said they were the same. Even if 875 bid is approved for some indication, it does not mean PK is not important for amox. As a matter of fact, the approval may be based upon the results of PK studies. If you just goolgle amox + PK, there are a whole bunch of studies out there.

There are two types of adverse reactions. The first is idiosyncratic as in unexpected and unrelated to it's therapeutic effect. The second and most common are just an extension of the therapeutic effect. Unless you are anybody else can show me what effect the penicillin will have on a human being I think you are over thinking this. Just as I was able to point out the reason why we get side effects from drugs that effect the 50S sub unit even though we don't have the 50S sub unit in most cells, I would like you to show me on a cellular level how a penicillin over dose works and what the pharmacokinetics would be. I assume there has to be a certain dose that overwhelms the kidneys and allows for toxic levels. What would that dose be? As cycloketocaine has pointed out doses of 50 mg/kg/day once daily have been studied. That's a single 3.5gm daily dose.
 
OT...i dont think the beef here is not drug target (PD), it is you trying to discredit PK in the Amoxil arguement. Now, thats jus not cool.

ADME dictates the fate of any and every compound that enters the human body. For drugs, its referred to as pharmacokinetics.
 
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OT...i dont think the beef here is not drug target (PD), it is you trying to discredit PK in the Amoxil arguement. Now, thats jus not cool.

ADME dictates the fate of any and every compound that enters the human body. For drugs, its referred to as pharmacokinetics.

Listen, even though I graduated from pharmacy school before you were born, I know what pharmacokinetics is. But since you want to be insulting and condescending to me I'll return the favor. Let me recap the thread for you. This is basically a discussion on why Amoxicillin is basically non-toxic to humans. There are two ideas put forward. The first is that because it is cleared so rapidly from the body it cannot build up to toxic levels. The second argument says the reason is there is no part of the human being affected by Amoxicillin, because we don't have cell walls. I'll stand by my response especially in light of the information supplied by cycloketacaine, the reason Amoxicillin is non-toxic is we don't have cell walls.
 
OT...much respect, actually didn't mean to come off as condescending, I was only trying to be stewie griffin silly while making a point.
 
OT...much respect, actually didn't mean to come off as condescending, I was only trying to be stewie griffin silly while making a point.

Even Back in the stone age they taught ADME.....
 
Help please!

Is amoxicillin 2000mg daily for 10 days too high or acceptable??
 
Never dispensed Augmentin XR at 2 grams BID, have you? I was prescribed that about a year ago, and it gave me massive diarrhea. I cut back to 1 gram BID and took it twice as long. And when THAT failed, I was put on Biaxin and that wasn't much fun either. Haven't had another sinus infection, though.
 
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