In most patients periodontitis is successfully treated by scaling and root planing, but some studies have shown that certain sites continue to show periodontal tissue destruction despite conventional periodontal therapy. To solve this problem, antibiotics may be administered as an adjuvant treatment. This includes azithromycin (AZM), which is effective against Gram-negative aerobic and anaerobic bacteria and has a long half-life in periodontal tissues. The purpose of the present study was to determine the efficacy of azithromycin as an adjuvant treatment for periodontitis through a review of the literature in Medline, Lilacs and Scielo, combining the keywords “azithromycin”, “periodontal treatment” and “periodontitis” in both Portuguese and English languages. To be included, articles had to be clinical trials, randomized, controlled, double-blind or blind, and published between 2001 and 2011. 70 articles were found, of which 12 were selected based on title and abstract. Most studies used AZM as an adjuvant treatment for chronic periodontitis, usually in a single daily dose of 500 mg over three days, and indicated that AZM significantly reduced probing depth and increased periodontal attachment when compared to controls. Furthermore, a reduction in red and orange complex and an increase in bacteria associated with healthy periodontal conditions were observed in subjects treated with AZM. It may be concluded that the use of AZM as an adjuvant treatment for periodontitis improves clinical and microbiological parameters when compared to conventional treatment alone.