According to embodiments of the present disclosure, a method of treating, preventing or ameliorating acute alcoholic liver damage in a subject comprises administering to the subject an exogenous source of nicotinamide adenine dinucleotide (NAD+) comprising NADH (nicotinamide adenine dinucleotide (NAD)+hydrogen (H)) or NRH (dihydronicotinamide nucleoside). Administration of the exogenous source of NAD+ may also be used to increase a subject's tolerance to alcohol, and/or to treat, prevent or alleviate the symptoms of an alcohol hangover.