According to a randomized clinical trial, using active transcutaneous electrical nerve stimulation (TENS) prior to Propofol injection dramatically decreased both the occurrence and severity of pain when compared to sham TENS in patients scheduled for elective dental surgery under general anesthesia. The goal of the study was to see if TENS might lessen pain during Propofol injections when contrasted to sham TENS.

A total of 80 subjects (aged 19–70 years) were divided into the active TENS group, which used two electrodes on the site of venous cannulation to receive electrical stimulation, and the sham TENS group, which did not receive any stimulus. Propofol 0.5 mg/kg was administered through an intravenous route 20 min after TENS. Utilizing a four-point score (0 = none, 1 = mild, 2 = moderate, 3 = severe), an evaluation of pain was done. TENS-related adverse effects were also noted.

In general, there was a 47.5% overall incidence of pain during the Propofol injection in the TENS group compared to the sham group (87.5%). In comparison to the sham TENS group (42.5%), the TENS group's incidence of moderate pain (7.5%) was considerably reduced. The use of TENS did not result in any complications. Therefore, pretreatment with conventional TENS was promising to relieve Propofol injection pain.