Infective endocarditis is a frequent complication in intravenous drugs abusers. It is evident that in recent years this problem has increases as a consequence of the growing number of drug addicts. We review the clinical files of patients who entered the Regional General Hospital No. 20 IMSS in the City of Tijuana Mexico between May 1994 and May 1998 with diagnosis of infective endocarditis and had evidence intravenous abuse. Eight patients were included in the study. None of them had preexisting valve abnormalities. The infection involved right-sided values in 62.5% of cases left-sided values in 12.5%, and both sides in 12.5% of cases Staphylococcus aureus was the infecting germ in 50% of the cases. Survival of patients with right infective endocarditis was 75% and only 25% of them required surgical intervention. The mortality of infection in left side was 75% and 100% if infection involved both sides. Infective endocarditis in drugs abusers has a favorable prognosis when right sided valves are affected. Mortality rates are higher in patients with left-sided involvement.