Side-effects due to the intravenous infusion of erythromycin lactobionate

A double-blind study was designed to test the hypothesis that local side-effects during i. v. administration of erythromycin lactobionate depend on the drug concentration and that they can therefore be minimized by dissolving erythromycin in a larger infusion volume. Forty healthy students were assigned in a randomized sequence to four 30 min infusions: 120 and 250 ml of erythromycin lactobionate (1 g in 0.9% NaCl) and 120 and 250 ml of placebo (0.9% NaCl). An unexpectedly high incidence (95% and 80% for the infusion volumes of 120 and 250 ml, respectively) of severe systemic side-effects was observed during the first 79 infusions. Because all of these systemic side-effects were associated with the infusion of erythromycin, the study was terminated at this point. Side-effects included abdominal cramps, nausea, vomiting, dizziness and profuse sweating. The postulated positive effect of lower erythromycin concentrations in the infusion on local side-effects (pain at the infusion site, erythema) was marginal (63% vs. 45%). Compared to the systemic side-effects, the problem of local tolerance is less important. In young adults, 30 min infusions of 1 g erythromycin lactobionate are associated with a high incidence of systemic side-effects which may be due to an age-dependent effect of the drug on smooth muscle.