Pain on injection of propofol is a common side effect. The present study was designed to investigate the effect of esmolol on pain on propofol injection and to compare it with remifentanil and placebo.

In a double-blind, prospective trial, 120 patients scheduled to undergo elective surgery were randomized to receive normal saline (n=30), remifentanil 0.35 μg/kg (n=30), esmolol 0.5 mg/kg (n=30), or Esmolol 1mg/kg (n=30) as pretreatment. Thirty seconds after pretreatment, 25% of the total calculated dose of propofol (2 mg/kg) was administrated into a dorsal hand vein. Ten seconds after propofol had been given at the rate of 0.5 ml/sec pain was assessed on a four-point scale (0=none, 1 = mild, 2= moderate, 3= severe).

Inclusion Criteria:

• patients aged 19-60 years, American Society of Anesthesiologists (ASA) physical status I and II, scheduled for elective surgery under general anesthesia

Exclusion Criteria:

• Patients with cardiovascular, neurological or psychiatric disorder problem, patients who received the analgesic or sedative medications within the last 24 hours, and pregnancy were excluded