Patients sometimes notice an onion or garlic taste before losing consciousness with thiopentone. An assessment of 113 patients revealed that 42% of patients noticed this taste. The effect was observed less in older patients. There was no statistically significant difference in the incidence between men and women. Premedicated patients had a lower incidence, but this was explained by the greater proportion of older patients receiving a premedication. If the taste effect of thiopentone is genetically determined then it is a different gene to thiocarbamate which has about 75% tasters.
