Cannabis
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
Ginseng increases the clearance of
alcohol from the body and lowers blood
alcohol levels.
The
clinical significance of this interaction is unclear.
Kava
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
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.