How do I reduce injection pain


Review question

Is lidocaine injected intravenously (directly into a vein) effective in reducing the pain by injecting propofol, which is used to induce general anesthesia in adults?


Propofol is an anesthetic that is given to induce and maintain anesthesia for surgery in adults. Propofol is a popular induction medication because it provides steady induction and faster elimination than other medications such as thiopental. The main disadvantage of Propofol is that it is very painful to inject, as Propofol is usually injected into a hand vein and can cause skin irritation. This can make the anesthetic experience uncomfortable. One way to prevent this propofol-induced pain is to either give lidocaine before the propofol injection or to mix it with the propofol. Lidocaine is a widely used, inexpensive local anesthetic. The aim of this review is to find out how effective lidocaine is at reducing the severe pain caused by injecting Propofol.

Study characteristics

We searched the databases through October 2014. We included 85 studies, of which 82 (10,350 subjects) were eligible for quantitative analysis. Study participants were randomly selected to receive either intravenous lidocaine or normal saline (placebo) at the same time as their propofol injection.

We repeated the search in November 2015. We found 11 other relevant studies. These studies have been added to the list of studies for "anticipated classification" and will be fully included in the official review results when we update the review.

Sources of funding for the studies

Three of the 85 studies were funded either by a pharmaceutical company with a commercial interest in the results of the studies or by the manufacturer of propofol. Eight studies were supported by a government hospital or university budget, and one study was funded by a charitable grant.

Main results

We found that intravenous injection of lidocaine, either mixed with propofol or injected prior to propofol injection, was effective in reducing the incidence and high pain level of propofol injection pain. Adverse effects such as inflammation (redness, swelling) of the vein at the injection site were rare and were not more common in two studies when lidocaine was used. No study reported patient satisfaction.


Based on these results, we would expect that out of 1,000 patients who received intravenous propofol, approximately 384 who did not receive lidocaine would experience moderate to severe pain compared to only 89 patients who received lidocaine.

Quality of the evidence

In general, the quality of the evidence was high and showed great beneficial effects from the administration of lidocaine to reduce the injection pain of propofol.