Erythromycin breath test

The erythromycin breath test, provided by Metabolic Solutions, is a rapid and a quantitative measure of in vivo CYP3A4 activity. The test is for designed... 

Tateishi, T., Graham, S. G., Krivoruk, Y., and Wood, A. J. J. (1995) Omeprazole does not affect measured CYP3A4 activity using the erythromycin breath test. Bn J. Clin. Pharmacol. 40, 411-412. 

Lown KS, Kolars JC, Thummel KE, et al. Interpatient heterogeneity in expression of CYP3A4 and CYP3A5 in small bowel. Lack of prediction by the erythromycin breath test. Drug Metab Dispos 1994 22 947-955. 

Watkins PB, Murray SA, Winkelman LG, et al. Erythromycin breath test as an assay of glucurocorticoid-inducible liver cytochromes P450. J Clin Invest 1989 83 688-697. 

Watkins PB, Hamilton TA, Annesley TM, et al. The erythromycin breath test as a predictor of cyclosporin A blood levels. Clin Pharmacol Ther 1990 48 120-129. 

Krivoruk Y, Kinirons MT, Wood AJJ, et al. Metabolism of cytochrome P4503A substrates in vivo administered by the same route lack of correlation between alfentanil clearance and erythromycin breath test. Cbn Pharmacol Ther 1994 56 6084)14. 

Watkins PB, Turgeon DK, Saenger P, et al. Comparison of urinary 6-beta-cortisol and the erythromycin breath test as measures of hepatic P450IHA (CYP3A) activity. Clin Pharmacol Ther 1992 52 265-273. 

Stein CM, Kinirons MT, Pincus T, et al. Comparison of the dapsone recovery ratio and the erythromycin breath test as in vivo probes of CYP3A activity in patients with rheumatoid arthritis receiving cyclosporine. Clin Pharmacol Ther 1996 59 47-51. 

Kinirons MT, Krivoruk Y, Wilkinson GR, et al. Effects of ketoconazole on the erythromycin breath test and the dapsone recovery ratio. Br J Clin Pharmacol 1999 47 223-224. 

Turgeon DK, Normolle DP, Leichtman AB, et al. Erythromycin breath test predicts oral clearance of cyclosporine in kidney transplant recipients. Clin Pharmacol Ther 1992 52 471 178. 

Turgeon DK, Leichtman AB, Blake DS, et al. Prediction of interpatient and intrapatient variation in OG 37-325 dosing requirements by the erythromycin breath test a prospective study in renal transplant recipients. Transplantation 1994 57 1736-1741. 

Cheng CL, Smith DE, Carver PL, et al. Steady-state pharmacokinetics of dela-virdine in HIV-positive patients effect on erythromycin breath test. Clin Pharmacol Ther 1997 61 531-543. 

Wagner D. CYP3A4 and the erythromycin breath test. Clin Pharmacol Ther 1998 64 129-130. 

McCrea J, Prueksaritanont T, Gertz BJ, et al. Concurrent administration of the erythromycin breath test (EBT) and oral midazolam (MDZ) as in vivo probes for CYP3A activity. J Clin Pharmacol Ther 1999 39 1212-1220. 

C- erythromycin breath test or ERMBT CYP3A4 catalyzes the N-desmethylation of [14C N-methyl] erythromycin. The test consists in the measurement of a single breath expired 14C02 collection obtained at 20 minutes following the iv administration of a 0.03 mg... 

Rivory LP, Slaviero KA, Seale JP et al. (2000) Optimizing the erythromycin breath test for use in cancer patients. Clin Cancer Res 6 3480-3485... 

Lown K, Kolars J, Turgeon K, et al. (1992) The erythromycin breath test selectively measures P450IIIA in patients with severe liver disease. Clin Pharmacol Ther 51 229-238. 

PK = pharmacokinetic Cl = clearance AUC = area under the plasma concentration vs. time curve ERBT = erythromycin breath test IM = intramuscular IV = intravenous... 

The occurrence of an interaction in a particular patient is difficult to predict. Hepatic concentrations of CYP3A4, the activity of which can be estimated by an erythromycin breath test (133), vary at least ten-fold among patients (136,137). 

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