PHARMACOKINETIC PROPERTIES OF BROMIDE IN DOGS AFTER THE INTRAVENOUS AND ORAL-ADMINISTRATION OF SINGLE DOSES

Bromide (20 mg kg(-1)) was administered intravenously and orally to normal beagle dogs. The mean (so) apparent elimination half life (t(1/2 beta)) after oral administration (46 +/- 9 days) was not significantly different from the mean t(1/2 beta) after intravenous administration (37 +/- 10 days). The mean total body clearance was 9.0 +/- 3.9 ml day(-1) kg(-1) and the mean apparent volume of distribution was 0.45 +/- 0.07 litre kg(-1). The mean area under the serum concentration time curve (AUC) was significantly smaller after oral administration than after intravenous administration, and from a comparison of the two values the oral bioavailability of bromide was estimated to be 46 per cent. Assuming this degree of bioavailability, the daily dose of bromide necessary to maintain serum bromide concentrations within the therapeutic range of 1000 to 2000 mg litre(-1) recommended for epileptic dogs was estimated to be approximately 21 mg kg(-1). The intravenous loading dose of sodium bromide necessary to reach minimal therapeutic serum bromide concentrations was predicted to be 570 +/- 90 mg kg(-1).