It is widely believed that people who abuse alcohol can sustain a liver injury after taking doses of acetaminophen just above the recommended maximum dose. This study is designed to look at the interaction between acetaminophen, liver injury and alcohol abuse. Subjects will undergo baseline tests to ensure that they do not have liver damage at the time of enrollment. Each subject will be randomly assigned to receive either a therapeutic dose of acetaminophen or a placebo three times a day for four days. Subjects will have blood work drawn on a daily basis to monitor the status of the liver. These tests will include conventional markers of liver injury in addition to a novel biomarker of liver function, a-GST. Previous work in the investigators' group has shown that a-GST is a more sensitive indicator of liver injury following acetaminophen overdose (Sivilotti 1999, Sivilotti 2002 x 2). However, it has never been used to study the alcoholic population. The investigators believe that a-GST may detect a subclinical acetaminophen-induced liver injury that has previously gone unrecognized in the alcoholic population.