Erythromycin interactions

Erythromycin interacts with simvastatin, probably by inhibiting its metabolism by CYP3A4. In a randomized, double-blind crossover study in 12 healthy volunteers, erythromycin significantly increased mean peak serum concentration and AUC for both unchanged simvastatin and its active metabolite simvastatin acid. However, there was extensive interindividual variability in the extent of this interaction (50). 

Freeman J, Martell R, Carrufhers S, et al. Cyclosporin-erythromycin interaction in normal subjects. Br J Clin Pharmacol 1987 23 776-778. 

Berndt A, Gramatte T, Kirch W. Digoxin-erythromycin interaction In vitro evidence for competition for intestinal P-glycoprotein. Eur J Pharmacol 1996 50 538. 

Bartle WR. Possible warfarin-erythromycin interaction. Arch Intern Med 1980 140(7) 985-7. 

Hedrick R, Williams F, Morin R, Lamb WA, Cate JC 4th. Carbamazepine-erythromycin interaction leading to car-bamazepine toxicity in four epileptic children. Ther Drug Monit 1983 5(4) 405-7. 

Wroblewski BA, Singer WD, Whyte J. Carbamazepine-erythromycin interaction. Case studies and clinical significance. JAMA 1986 255(9) 1165-7. 

Gupta SK, Bakran A, Johnson RW, Rowland M. Cyclosporin-erythromycin interaction in renal transplant patients. Br J Clin Pharmacol 1989 27 475-481. 

Bussey HI, Knodel LC, Boyle DA. Warfarin-erythromycin interaction. Ardi Intern Med... 

Information about the clarithromycin or erythromycin interactions with methylprednisolone is much more limited than with the interaction between troleandomycin and methylprednisolone, but they all appear to be established and of clinical importance. The effect should be taken into account during concurrent use and appropriate dosage reductions made to avoid the development of corticosteroid adverse effects. The authors of one study suggest that this reduction should be empirical, based primarily on clinical symptomatology. Another group found that a 68% reduction in methylprednisolone dosage was possible within 2 weeks. Troleandomycin appears to have a greater effect than erythromycin or clarithromycin. 

Claesson K, Brattstrom C, Burke JT. Sirolimus and erythromycin interaction two cases. Transplant Proc (2001) 33,2136. 

Hie replicase of virus Q() (an RNA-phage) consists of four subunits one is encoded by the vM genome, wliile tlie other three are the host proteins EFTu, EFTs and R.p. SI. The Fig. shows a three dimensional model for the arrangement of R.p. in the SOS-subunit. Many antibiotics act by combining with R.p., e.g. streptomycin interacts with S12, and bacterial mutants resistant to streptomycin have been shown to liave an altered S12. Erythromycin interacts with L22, spiramycin with LA. 

Binding studies have confirmed the specificity of erythromycin interaction with the 50 S ribosome subunit, the requirement of monovalent ions and the lack of binding by 42 S nucleoprotein cores derived from the 50 S particles. Lincomycin inhibition of peptide bond formation has been confirmed whereas it was concluded that erythromycin inhibits translocation by acting on the 50 S subunit whereas streptomycin inhibits this step by acting on the 30 S subunit , ... 

Erythromycin Tablets 250, 500 mg 500 mg twice daily with food Maintenance dose 500 mg daily Gl intolerance, drug interactions... 

Erythromycin- sulfisoxazole 50 mg/kg per day of erythromycin component in 3 4 doses Nausea, vomiting, abdominal pain, diarrhea, rash SS Many drug interactions (like clarithromycin), contraindicated in children under 2 months increasing pneumococcal resistance... 

Drug interactions Metabolized by CYP450 3A4 (e.g., cyclosporine, erythromycin, itraconazole, phenytoin, St. John s wort)... 

Carbamazepine may interact with other drugs by inducing their metabolism. Valproic acid increases concentrations ofthe 10,11-epoxide metabolite without affecting the concentration of carbamazepine. The interaction of erythromycin and clarithromycin (CYP3A4 inhibition) with carbamazepine is particularly significant. 

Interactions Antacids ciclosporin colestipol druas metabolized bv cytochrome P450 3A4 fibrates oral-contraceptiyes warfarin niacin erythromycin diaoxin azole-antifunaals... 

Cimetidine, erythromycin, and dextropropoxyphene had no effect on the pharmacokinetics of MHD. Results with warfarin show no evidence of interaction with either single or repeated doses of oxcarbazepine. 

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