Self-perceived side-effects of metronidazole during periodontal treatment

Objective: The purpose of this investigation was to evaluate the use of systemically administered metronidazole during periodontal treatment, regarding its side effects. Method: Fifty-four subjects (mean age 46.4 ± 8), with chronic periodontitis (8 sites with probing depth >5mm) were selected. Plaque accumulation (0/1), bleeding on probing (0/1), probing pocket depth and clinical attachment level were monitored prior to therapy and 90 days post-therapy. After receiving full mouth scaling and root planing subjects were randomly assigned to a test (T, n=27) and a control group (C, n=27). Subjects in the test group received 400mg of systemically administered metronidazole 3 times/day, for 10 days. The control group received placebo. In order to evaluate possible side effects of metronidazole, a questionnaire of 13 items was applied at the end of the drug/placebo administration. Result:There were no significant differences between groups for clinical parameters at baseline (Mann-Whitney test). 67% of subjects in the test group and 33,3% in the control group reported some physical impact as discomfort, nausea, diarrhea, metallic taste, migraine or drowsiness (p<0.05, X² test). Considering the side effects separately, metallic taste (T=85% and C=12.5%) and lack of energy (T=100% and C=0%) have shown statistically significant differences for the impacts (p<0.05, X² test). Conclusion:These results suggest that ingestion of metronidazole at the dosage here described causes side effects, the most noticeable ones being metallic taste and lack of energy.