We designed a study to compare breath alcohol values (BrAV) and blood ethanol concentrations (BEC) following ingestion of an ethanol-containing cough-cold preparation.

Materials and Methods. We recruited 6 healthy adult volunteers. Prior to participation, each subject refrained from medications and ethanol for 24 h and fasted for 2 h. An indwelling intravenous catheter was placed, and a baseline BEC (EMIT assay) was obtained. Each subject also exhaled into a breath alcohol measuring device (Alco-Sensor III, Intoximeters, Inc.). Subjects then drank a standard 1-ounce dose of a cough-cold preparation, containing ethanol 10%, doxylamine, dextromethorphan, pseudoephedrine, and acetaminophen (Vicks Nyquil). Repeat BrAV and BEC were determined at 10, 15, 20, 30, 60 and 90 min.

Results. All 6 subjects had BEC below the laboratory's limit of detection (<10 mg/dL) for all 7 samples. Three subjects had BrAV of 0 mg/dL for all samples, while 3 had values as follows: Table

Table 1
Full size table

Discussion. Accurate correlation between BrAV and BEC depends on a theoretical ratio of alveolar gas to blood ethanol, approximately 1:2100. Breath alcohol measuring devices, however, may produce false positive results if ethanol residues from a recently-ingested sample remain. We chose sample times to reflect sample “wash-out” from the mouth, but also systemic absorption of the ingested dose. We included the 15-min sample to comply with Department of Transportation guidelines for breath alcohol analysis.

Conclusion: Ingestion of a standard 1-ounce dose of a cough-cold preparation, containing ethanol 10% (ethanol dose = 2.4 g), does not result in significant BrAV or BEC.

(Funded by a grant from the American Academy of Clinical Toxicology and Texaco)