To assess the local and systemic intracoronary (IC) ergonovine maleate (EM), single or repeated 25 micrograms bolus injections were administered to 108 consecutive patients with chest pain and normal coronary arteriograms. Coronary artery spasm (CAS) was induced in 17 (15.7%) patients. None of these patients developed ST-segment depression, and ST-segment elevation appeared in only 6 (35.3%). In 59 of the 91 patients without CAS, both the IC and the intravenous (IV) EM arteriographic and hemodynamic effects were compared. The mean diameter of the vessels was reduced by 15% (p less than 0.001) after two single 25 micrograms ICEM injections. Only insignificant changes were induced in the heart rate (baseline 80 +/- 15; after ICEM 79 +/- 15 beats/min; p = NS) and systolic aortic pressure (baseline 147 +/- 27; after ICEM 149 +/- 28 mmHG; p = NS). Following 350 micrograms of cumulative IVEM, the mean coronary diameter decreased by 20% (p less than 0.01 vs. ICEM dose) and the heart rate diminished slightly (76 +/- 12 beats/min, p less than 0.01). However, the systolic aortic pressures did increase by 16% (171 +/- 28 mmHg; p less than 0.001). No major complications were observed. Thus, to induce CAS the IC delivery route appears to be safe, allows for more accurate titration, and adverse systemic effects, such as hypertension, are avoided.