Oral Care A major origin of contamination of oral secretions is due to colonization of dental plaque and oropharynx with respiratory pathogens (Khezri et al., 2014). Usage of remarkable antiseptic mouthwashes directed against gram negative and positive microorganisms can decrease the rate of VAP (Pugin et al., 1991, DeRiso et al., 1996). Antibacterial mouthwashes are utilized in many clinical conditions for prophylactic and therapeutic purposes. The mouthwashes most commonly conveyed in the literature, including hydrogen peroxide, sodium bicarbonate, sodium chloride 0.9 %, water, povidone-iodine, and chlorhexidine (CHX). A review of the common oral rinses in the critical intubated patients is provided as follows: Hydrogen Proxide Hydrogen peroxide is a reactive oxygen species (ROS), clear, colourless and odour-free solution. It is completely soluble in water and gives an aciditic solution (Berry and Davidson, 2006). Fischman SL et al., showed that hydrogen peroxide has antimicrobial effects with slight or no adverse effects. The concentration of hydrogen peroxide debated was 1.5% and 3%, and suggested that it often be used in combination with other substances (Marshall et al., 1995). In the study, thirty-five normal subjects were randomly assigned to wash with hydrogen peroxide oral rinse, then significant mucosal abnormalities were detected. The results of this study showed that there were numerous subjective complaints of discomfort in the hydrogen peroxide groups, although this study was not unbiased (Berry and Davidson, 2006). Moreover, Holberton et al stated that some ICU patients found hydrogen peroxide mouthwashe refused to use it (Holberton et al., 1996). Hydrogen peroxide oral wash has been used for many years in ICU patients. Although, their effectiveness has not been thoroughly evaluated for the provision of oral care in critically ill patients. Hydrogen peroxide has antimicrobial properties and mechanical cleaning of debris, but current evidence suggests it harms the oral mucosa and provokes many negative reactions (such as oral mucositis), so it is not recommended (Coleman, 2002).