Echinacea Mouthwash More Effective than Chlorhexidine in Decreasing Oral Microbial Load in Intubated Patients

Ventilator-associated pneumonia (VAP) is a common bacterial infection among patients in intensive care units (ICUs). For patients placed on a ventilator, the risk for nosocomial pneumonia and mortality is higher than for other patients. The use of anti-bacterial mouthwashes is recommended to prevent the occurrence of VAP. Among the available mouthwashes, chlorhexidine is highly effective in reducing dental plaque and pathogenic microorganisms; however, studies investigating the efficacy of chlorhexidine for the prevention of VAP have yielded conflicting results. Extracts of echinacea (Echinaceaspp.Asteraceae) aerial parts have immuno-stimulant, anti-inflammatory, and mild antimicrobial properties. This double-blind, randomized, controlled clinical trial compared the effects of echinacea and chlorhexidine mouthwashes on the oral microbial load in ICU patients who underwent tracheal intubation.

The study included 70 patients admitted to the ICUs in three hospitals in Arak, Iran, between April 2014 and October 2014 who underwent intubation. The patients were randomly assigned to either the intervention group (n=35) or the control group (n=35). Exclusion criteria were not reported.

Baseline demographic data, patient history, the cause of hospitalization, and medications were recorded. All patients received the normal care protocol which included saline rinses and suctioning of secretions every two to three hours. All areas of each patient’s mouth were brushed twice daily with a toothbrush. Before and after brushing each section of the mouth, 15 mL of either 0.01% echinacea or 0.2% chlorhexidine mouthwash was applied and then suctioned in less than 30 seconds.

To prepare the echinacea mouthwash, the dried herb was soaked in water for 60 hours. The solution was filtered and then maintained at 104-111.2° F (40-44° C) for solvent evaporation. The authors report that the final solution (solvent not specified) contained 95 g dried herb per mL; however, this is likely a reporting error. The authors cite a previous study regarding the preparation method which appears to have used a final solution containing 95 mg/mL. Elsewhere, the authors also mention preparation of a 1% solution and using a 0.01% solution. Based on this poor reporting, it is unclear what was actually prepared and used. The species of echinacea used in this study also was not specified. The source of the echinacea was not reported.

Before and after each mouthwash application, 50 μL samples of aspirated secretions were collected from the back of the mouth. Normal saline was added to the sample to reach a volume of 1 mL; 10 μL of that solution was incubated overnight on blood agar plates. The number of colony-forming units (CFU) was counted, and the results were expressed as the base 10 logarithms of the concentration (log CFU/mL). Secretion samples were collected ≤ 12 hours after admission and then every 12 hours during the intervention. Post-test samples were collected four days after the last intervention.

Most (67.1%) of the patients were male, with an average age of 44.9 years. For 52.8% of the patients, trauma was the cause of hospitalization. Before the intervention, no significant between-group differences were observed for age, sex, smoking history, admitting hospital, blood pressure, respiratory and heart rates, or the number of teeth.

Before the intervention, the mean (standard deviation) oral microbial counts were 6.21 (0.75) in the intervention group and 6.43 (0.47) in the control group (P=0.1). Four days after admission, the oral microbial counts were 4.75 (0.96) in the intervention group and 5.26 (0.80) in the control group (P=0.01).

The authors conclude that compared with the chlorhexidine solution, “the echinacea solution was more effective in decreasing the oral microbial flora of patients in the intensive care unit.”

The authors report no conflicts of interest.


Safarabadi M, Ghaznavi-Rad E, Pakniyat A, Rezaie K, Jadidi A. Comparing the effect of echinacea and chlorhexidine mouthwash on the microbial flora of intubated patients admitted to the intensive care unit. Iran J Nurs Midwifery Res. November-December 2017;22(6):481-485. doi: 10.4103/ijnmr.IJNMR_92_16.