Clinical Question: In the office, are triethanolamine oleate or carbamide peroxide ear drops more effective than irrigation with an isotonic salt solution in the removal of impacted cerumen?

Setting: Outpatient (any)

Study Design: Randomized controlled trial (double-blinded)

Allocation: Uncertain

Synopsis: Researchers compared the use of triethanolamine oleate and carbamide peroxide with an isotonic salt solution irrigation in 77 patients with excessive cerumen ranging from mild wax buildup to complete occlusion of the ear canal. The participants were assigned to treatment in the affected ear, followed after 15 minutes with 50 mL of lukewarm water irrigation using an oral jet irrigator (see note below). If the treatment was ineffective, it was repeated a second time.

Fewer than 10 percent of participants in either treatment group had successful removal of cerumen after one application. After two treatments, the total percentage of participants with no occlusion did not differ significantly among the three groups, ranging from 15 percent (carbamide peroxide) to 42 percent (isotonic solution). Unfortunately, the researchers did not perform a power calculation, so it is unclear whether the study was capable of finding a difference if one existed.

Because the researchers did not look for a degree of improvement, but rather used the outcome of no occlusion versus mild to complete occlusion as their end point, there could have been incremental improvement that was not documented in this study. These results add to the general confusion in the literature on this subject; several conflicting trials exist regarding the effectiveness of these and other products, such as docusate liquid and sodium bicarbonate 10 percent solution (Burton MJ, Doree CJ. Ear drops for the removal of ear wax. Cochrane Database Syst Rev 2004;(4):CD004326). These results apply to office use; typically, patients using these products instill them several times a day for several days. In the office, however, a quicker response is needed.

Bottom Line: Two commonly used products—triethanolamine oleate and carbamide peroxide—are no more effective than placebo in aiding irrigation in the removal of cerumen from occluded ear canals in the office setting. Other options, such as docusate liquid and sodium bicarbonate, also have been studied with conflicting results. (Level of Evidence: 2b)

note: The researchers used the lowest pressure setting of the oral jet irrigator. Although no problems occurred in this study, use of an oral jet irrigator has caused damage to ear structures in other reports.