Comparative plasma and tissue drug concentrations in L. donovani-infected and uninfected BALB/c mice up to 48 h after administration of single dose AmBisome. AmBisome was administered to BALB/c mice, naive (A, C, E, G, and I) or infected with L. donovani for 33 days (B, D, F, H, and J), and amphotericin B (AmB) concentrations were determined in plasma (A and B), liver (C, D, G, and H), and spleen (E, F, I, and J) at 5 min and 4, 24, or 48 h after drug administration. Amphotericin B concentrations are presented as nanograms per gram of tissue (C to F) or total amphotericin B concentration per organ (G to J). Total amphotericin B concentrations per organ were calculated as follows: organ weight in grams (as determined at sacrifice) × amphotericin B concentration in nanograms per gram of tissue (as measured after processing of whole organs). Each symbol represents data from an individual mouse. Horizontal lines indicate the mean (n = 3/group) and error bars the standard deviation (SD).