AIM: This systematic review and meta-analysis evaluated the effect of using nonsteroidal anti-inflammatory drugs (NSAIDs) before dental bleaching sessions in the dental office on postoperative sensitivity. METHODS: The review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses checklist and registered on International Prospective Register of Systematic Reviews under number CRD42020210054. Randomized clinical trials published in the English language that compared the preventive use of NSAIDs with a placebo on the sensitivity resulting from dental bleaching in the dental office were selected, with no limitation on the year of publication. The electronic searches took place in PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library and were carried out independently by two researchers. A total of 30 articles were obtained; seven were selected according to the inclusion criteria. RESULTS: No significant differences were found in the reduction of dental sensitivity between the experimental group compared to the placebo during the session (p=0.32; mean difference [MD]=-0.30; 95% CI, -0.88 to 0.29), immediately after the session (p=0.22; MD=-0.29; 95% CI, -0.75 to 0.17), up to 1 hour later (p=0.10; MD=-0.94; 95% CI, -2.06 to 0.18), and between 1 and 24 hours after the procedure (p=0.78; MD=-0.11; 95% CI, -0.90 to 0.68). The incidence of sensitivity between the groups also did not show statistically relevant differences (p=0.60; MD=1.15; 95% CI, 0.69-1.92). Furthermore, none of the studies reported side effects in any patient. CONCLUSION: This systematic review and meta-analysis indicates that the use of NSAIDs before dental office bleaching is not effective in reducing dental sensitivity during or up to 24 hours after the procedure. In addition, there was no difference in the incidence of sensitivity between the experimental and placebo groups.