Amoxicillin pharmacokinetics

Huisman-de Boer, J.J. van den Anker, J.N. Vogel, M. Goessens, W.H.F. Schoemaker, R.C. de Groot, R. Amoxicillin pharmacokinetics in preterm infants with gestational ages of less than 32 weeks. Antimicrob.Agents Chemother., 1995, 39, 431—434... 

Probenecid appears to completely inhibit the renal tubular secretion of the active metabolite of oseltamivir via the anionic renal transporter process. Oseltamivir does not alter amoxicillin pharmacokinetics, suggesting minimal potential to inhibit the renal anionic transport process. Cimetidine, which inhibits the renal tubular secretion of drugs via the cationic secretion transport process, had no effect on oseltamivir. 

Probenecid markedly increased the AUC of the active metabolite of oseltamivir, but because of the large safety margin of oseltamivir, this increase is not considered to be clinically relevant. " Oseltamivir did not alter amoxicillin pharmacokinetics, and is therefore unlikely to interact with other renally secreted organic acids. Other drugs that are involved in the active anionic tubular secretion mechanism are also unlikely to interact. Cimetidine does not interact with oseltamivir, and other drugs that are inhibitors of the renal cationic secretion transport process are unlikely to interact. ... 

Gotteries, J., Svenheden, A., Alpsten, M., Bake, B., Larsson, A. et al., Gastrointestinal transit of amoxicillin modified-release tablets and a placebo tablet including pharmacokinetic assessments of amoxicillin, Scand. J. Gastroenterol. 1996, 32, 49-53. 

Hoffman, A., et al. 1998. Pharmacodynamic and pharmacokinetic rationales for the development of an oral controlled-release amoxicillin dosage form. J Control Release 54 29. 

As resistance to 3-lactam antibiotics increased because of the expression of a variety of 3-lactamases, many groups focused their efforts on discovering compounds that could be more reactive to 3-lactamases without having significant intrinsic antibiotic activities of their own and pharmacokinetic properties that would be similar to 3-lactam antibiotics. This focus led to the discoveries of clavulanic acid (18) and monobactam sulfazecins (19). Nature effectively stabilized the latter monobactam structure by the addition of a A-sulfamic acid. The 3-lactamase inhibitor clavulanic acid was combined with amoxicillin, which... 

Parenteral preparations with antimicrobial activity, which depends on the causative pathogenic microorganism, and pharmacokinetic properties that meet most of these criteria include procaine penicillin G (aqueous suspension), amoxicillin trihydrate-clavulanate potassium combination (aqueous suspension), and enro-floxacin (solution). Enrofloxacin is not approved for use... 

In healthy subjects amoxicillin had no effect on the pharmacokinetics of oral oseltamivir (20). 

The pharmacokinetics of amoxicillin after oral [187,188] and parenteral [188,189] administration to humans, and after oral administration in combination with potassium clavulanate [190], have been reviewed. These reviews also cover antibacterial activity and therapeutic use. 

Gastrointestinal transit of amoxicillin modified-release tablets and a placebo tablet including pharmacokinetic assessments of... 

Regarding proton pump inhibitors, the effect of CYP2C19 PM status is not limited to pharmacokinetic alterations. The difference in the pharmacokinetics has been shown to influence the outcome of H. Pylori eradication therapy. Furuta et al. showed that in patients with confirmed H. Pylori infection treated with omeprazole or lansoprazole plus clarithromycin and amoxicillin, CYP2C19 PMs had an eradication rate of 97.8% compared with a rate of 72.7% (P < 0.001) for CYP2C19 EMs (51). 

The pharmacokinetic profiles of P-lactams dictate tissue depletion profiles. Concentrations are generally high in the kidney, very low in fat, and also low in muscle. For example, in pigs, Martinez-Larranaga et al. reported concentrations (mg/kg) of amoxicillin of 23.6 (muscle),... 

Non-linearity may arise at at any one of the various pharmacokinetic steps, such as absorption, distribution and/or elimination. For example, the extent of absorption of amoxicillin decreases with an increase in dose. For distribution, plasma protein binding of disop5Tramide is saturable at the therapeutic concentration, resulting in an increase in the volume of distribution... 

The pharmacokinetics of amoxicillin 1 g, and both amoxicillin and clavulanic acid (given as co-amoxiclav 625 mg), were not significantly altered by 10 doses of aluminium/magnesium hydroxide (Maalox) 10 mL, with the last dose given 30 minutes before amoxicillin. Another study found that four 40-mg doses of aluminium hydroxide (Aludrox) given at 20 minute intervals had no effect on the pharmacokinetics of either amoxicillin or clavulanic acid (given as co-amoxiclav 750 mg with the second dose of antacid). ... 

I. Amoxicillin and co-amoxidav. Food eaten immediately before amoxicillin reduced its serum levels by about 50% and reduced urinary excretion, when compared with the fasted state. However, in another study, a standard breakfast had no effect on the AUC of a single 500-mg dose of amoxicillin in 16 healthy subjects. Similarly, a crossover study in 18 healthy subjects given co-amoxiclav (amoxicillin 500 mg with clavulanic acid 250 mg), either 2 hours before or with a fried breakfast, found that the breakfast had no significant effect on the pharmacokinetics of amoxicillin or clavulanic acid. Moreover, a further study in 43 healthy subjects found that taking co-amoxiclav with food tended to minimise the incidence (but... 

Eshelman FN, Spyker DA. Pharmacokinetics of amoxicillin and ampicillin crossover study of the effect of food. Antimicrob Agents Chemother (1978) 14,539- 3. 

Cimetidine does not adversely affect the bioavailability of ampicillin or co-amoxiclav, but the bioavailability of oral benzylpenicillin may be increased in some subjects. Ranitidine does not affect the pharmacokinetics of amoxicillin, but may possibly reduce the bioavailability of bacampicillin. 

Cimetidine 200 mg, given three times daily the day before and with a single 200-mg dose of co-amoxiclav (amoxicillin with clavulanic acid), had no significant effect on the bioavailability of amoxicillin or clavulanic acid. Another study found that ranitidine (300 mg given the day before and 150 mg given with the antibacterial) had no effect on the pharmacokinetics of a single 1-g dose of amoxicillin. ... 

Aspirin, indometacin, phenylbutazone, sulfaphenazole and sulfinpyrazone prolong the half-Ufe of benzylpenicillin whereas chlorothiazide, sulfamethizole and sulfamethoxypyridazine do not. Some sulfonamides reduce oxacillin blood levels. Pirenzepine does not affect the pharmacokinetics of amoxicillin. 

Pirenzepine 50 mg given three times daily on the day before and with a single 1-g dose of amoxicillin had no significant effect on the pharmacokinetics of the antibacterial. ... 

Probenecid inhibits the renal secretion of the active metabolite of oseltamivir and marked raises its plasma levels, but this is not clinically relevant because of the wide safety margin of oseltamivir. There was no pharmacokinetic interaction between amoxicillin and oseltamivir, and cimetidine did not alter oseltamivir pharmacokinetics. 

No interaction normalfy occurs between digoxin and amoxicillin, cefazolin, cefuroxime, flucloxacillin, phenoxymethylpenicillin or ticarcillin/clavulanic acid. No pharmacokinetic interaction occurs between ampicillin and digitoxin. In contrast, one early study found that cefradine increased serum levels of digoxin. 

Mainz D, Bomer K, Koeppe P, Kotwas J, Lode H. Pharmacokinetics of lansoprazole, amoxicillin and clarithromycin after simultaneous and single administration JAntimicrob Chemoti-er(2002) 50.699-706. 

Esomeprazole, lansoprazole and omeprazole do not alter the pharmacokinetics of amoxicillin, and omeprazole does not alter bacampicillin bioavailability. Isolated reports describe glossitis, stomatitis and/or black tongue in a small number of patients when treated with lansoprazole and antibacterials, which included amoxicillin, clarithromycin and metronidazole. 

A study in 12 healthy subjects found no significant changes in the pharmacokinetics of amoxicillin 1 g twice daily when it was given with lansoprazole 30 mg twice daily and clarithromycin 500 mg twice daily for 4 days. Other randomised, crossover studies in a total of 36 healthy subjects also found no changes in the bioavailability or half-life of amoxicillin 1 g twice daily when it was given with clarithromycin 500 mg twice daily and either esomeprazole 20 mg twice daily or 40 mg once daily for 7 days. ... 

In other studies omeprazole caused a few small changes in the pharmacokinetics of bacampicillin and amoxicillin, but their bioavailabilities were not reduced, " and the use of amoxicillin with omeprazole had a synergistic effect on Helicobacter pylori eradication. Similarly, in another study, omeprazole 40 mg twice daily for 5 days did not affect the pharmacokinetics of amoxicillin 750 mg twice daily for 5 days, although the mean serum concentration of omeprazole was 12% lower and intragastric pH was slightly lower with the combination than with omeprazole alone. This was felt to be partly due to suppression of77. pylori ... 

The pharmacokinetics of amoxicillin do not appear to be affected by concurrent use of esomeprazole, lansoprazole and omeprazole, and omeprazole was not affected by amoxicillin. 

Dogterom P, van den Heuvel MW, Thomsen T. Absence of phannacokinetic interactions of the combined contraceptive vaginal ring NuvaRing with oi amoxicillin or doxycycline in two randomised trials. CUn Pharmacokinet(2005) 44,429-38. 

Ampicillin, with or without suibactam, and amoxicillin do not alter the pharmacokinetics of theophyiiine. 

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