Serum levels of interleukin-8 (IL-8) are increased in patients with alcoholic hepatitis and correlate with disease severity. The present study was aimed at investigating serum IL-8 levels in relation to different levels of alcohol consumption. Serum IL-8 was measured in (a) 459 individuals randomly selected from the general adult population, including 221 alcohol abstainers, 140 light drinkers (1-140 g/week), 53 moderate drinkers (141-280 g/week), and 45 heavy drinkers (>280 g/week), as well as (b) 137 alcoholics admitted to the hospital. The proportion of individuals with abnormally high (>10 pg/mL) IL-8 levels increased with alcohol use from 5.9% in abstainers to 10.7% in light, 13.2% in moderate, and 17.8% in heavy drinkers (P=0.004). This proportion was exceedingly high in alcoholics admitted to the hospital (70.1%, P<0.001 with respect to all other categories). Extremely high (>100 pg/mL) IL-8 levels were only observed among alcoholics, and were more frequent in females than in males (23.5% versus 9.7%, P=0.03) in spite of lower alcohol consumption among the former. These data indicate that the effect of alcohol on serum IL-8 levels begins with light-to-moderate drinking and is dose-dependent. Females may be more prone than males to develop extremely high IL-8 levels after heavy alcohol intake.