A Cochrane review included 11 trials with a total of 2 077 patients. Successful prevention was defined as the prevention of a relapse while receiving prophylaxis. Fluconazole was better than placebo (RR 0.61; 95% CI 0.5 to 0.74, 5 RCTs, n=599, NNT 4) or no treatment (RR 0.16; 95% CI 0.08 to 0.34, 1 RCT, n=65). Comparing continuous fluconazole treatment with intermittent treatment (RR 0.65, 95% CI 0.23 to 1.83; 2 RCTs, n=891), there was no significant difference between the two treatment arms. Chlorhexidine was compared with normal saline in a single study with no significant difference between the treatment arms.There were insufficient data about the effectiveness of clotrimazole, nystatin, amphotericin B, itraconazole or ketoconazole for prophylaxis of oropharyngeal candidiasis.
Comment: The quality of evidence is downgraded by study quality (several limitations in some studies) and upgraded by constant findings. The authors of the review state that the potential for resistant Candida organisms to develop, as well as the cost of prophylaxis, might impact the feasibility of implementation.