To evaluate the influence of temperature of the injected anesthetic solution on the development of tremor during epidural anesthesia, 66 patients divided in three homogeneous groups were evaluated: group I (n = 22; bupivacaine 4 degrees C), group II (n = 24; bupivacaine 20 degrees C), and group III (n = 24; bupivacaine 37 degrees C). The incidence of tremor was 20% (4 patients) in group I, 9% (2 patients) in group II and 12.5% (3 patients) in group III. No significant differences were found between the groups. The overall incidence was 13.6%. The epidural injection of 5 ml of saline at 37 degrees C achieved the attenuation and/or disappearance of tremor in three (3/4) group I patients (4 degrees C) and in one (1/3) group III patient (37 degrees C), whereas it was ineffective in one patient from group I and one from group III. In the two patients from group II (20 degrees C) and in one from group III (37 degrees C), tremor was self-limited. We conclude that the incidence of tremor during epidural anesthesia is not correlated with the temperature of anesthetic solutions, and that the epidural injection of saline at 37 degrees C may give some therapeutic benefit.