Reduction of oral flora with rifampin in healthy volunteers

Abstract

The effect of a short course of rifampin on the oral microflora was evaluated in 17 healthy volunteers. Salivary specimens were collected before and after two 600-mg doses of rifampin administered 6 h apart. Salivary bacteria were identified to species, and total quantitative colony counts were determined for each isolate. For all 17 subjects, treatment with rifampin led to a reduction in total bacterial colony counts; the mean inhibitory activity was 85.8% (range, 48.3 to 99.8%). Both aerobic and anaerobic bacteria were inhibited in every case: 45.5 to 99.8% for aerobic bacteria, mean inhibitory activity of 85.8%; 40.9 to 100% inhibition for anaerobic bacteria, mean inhibitory activity of 87.6%. However, total counts were reduced by .2 logarithms in only 18% of individuals; for aerobes, in 29%; and for anaerobes, in 41%. All classes of bacteria were inhibited, with mean inhibitory activities ranging from 8.4 to 99.9%. However, only streptococci, Haemophilus spp., Bacteroides spp., and aerobic and anaerobic gram-positive nonsporeforming rods were reduced in counts close to 2 logarithms after treatment with rifampin. Clinical studies are needed to clarify the significance of these in vitro data and to delineate a possible role for rifampin in preoperative prophylaxis of patients undergoing head and neck cancer surgery.

Early Specific Host Response Associated with Starting Effective Tuberculosis Treatment in an Infection Controlled Placebo Controlled Mouse Study

“…The activity of INH is quite specific for TB as it is a pro-drug that requires activation by M. tuberculosis KatG and killing of host microflora or other infectious agents is probably limited. RIF has a broader spectrum of activity [19] and has also been shown to reduce human microflora after only a few doses [20], thus a change in immunological response as a result of these effects cannot be excluded. Direct effects of the drugs on the host, e.g.…”