Smoking cannabis (marijuana) may reduce and delay peak alcohol
levels. The effects of drinking alcohol
and smoking cannabis appear to be at least additive on driving performance, although some limited evidence suggests that regular cannabis use does not potentiate the effects of alcohol
The degree of impairment will depend on the individual patient. However, patients should be aware of the potential additive effects, and counselled against driving or undertaking other skilled tasks.
Ginseng increases the clearance of alcohol
from the body and lowers blood alcohol
significance of this interaction is unclear.
There is some evidence that kava may worsen the deleterious effects of alcohol
The effects of this interaction are not clear, but as some psychomotor impairment occurs warn all patients of the potential effects, and counsel against driving or undertaking other skilled tasks. The use of kava is restricted in the UK because of reports of idiosyncratic hepatotoxicity.
Liv.52, an Ayurvedic herbal remedy, appears to reduce the hangover symptoms
after drinking. However it also raises the blood alcohol
levels of moderate drinkers (by about 30%) for the first few hours after drinking.
Increases of up to 30% may be enough to raise the blood alcohol
from legal to illegal levels when driving. Moderate drinkers should be warned.