We appreciate the comments made by Dr. Jones on our recent article [1] about the lack of interaction between histamine-2-receptor antagonists and orally ingested ethanol.

Dr. Jones is correct in noting that the breath ethanol values given in our article actually represent an estimation of blood ethanol concentration. This was clearly stated in the legend to Figure 4: "Values determined using the Lion Alcolmeter actually represent blood ethanol concentrations." We felt that referring to these values as breath ethanol, rather than blood ethanol, would be less confusing for most readers.

Dr. Jones suggests that "error" may account for the higher values obtained using the breath analyzer compared with those obtained using gas chromatography. We believe these differences reflect well-known methodologic problems associated with breath analyzers that have been previously reported by Dr. Jones [2]. In our study, ethanol was given orally, in contrast to those in which ethanol was administered intravenously. Thus, despite extensive rinsing of the mouth and pharynx, it is certainly possible that residual oral ethanol contributed to the slightly higher readings observed with the breath analyzers. It is for these reasons that our conclusions were based on data obtained from head-space gas chromatographic measurements of ethanol concentration. Nevertheless, as Dr. Jones points out, it is evident from our study that regardless of the method used to measure ethanol, there is no clinically important interaction between ethanol and histamine-2 blockers.