Effect of azithromycin on gingival overgrowth induced by cyclosporine A + nifedipine combination therapy: A morphometric analysis in rats

Background: Drug-induced gingival overgrowth (DIGO) is a well-known adverse effect of cyclosporine A (CsA) and nifedipine (Nf) therapy. The aim of the present morphometric study was to evaluate the effect of azithromycin (Azi) on the combined GO in rats induced by CsA + Nf combination.

Materials and methods: Thirty Sprague-Dawley male rats were randomly divided equally into three groups. Group 1 (control) received olive oil only; Group 2 received a combination of CsA and Nf in olive oil throughout the study period; Group 3 received CsA + Nf combination therapy, and Azi was added for 1 week in the 5^th week. All the drugs were delivered by oral route. Impressions of the mandibular central incisal regions were taken, and study models were prepared at baseline and biweekly up to the 8 weeks. Statistical analysis was done by one-way analysis of variance and intergroup comparisons were made using Tukey's post hoc analysis.

Results: Significant GO was evident in Group 2 and Group 3 rats when compared to Group 1. However, in Group 3 (Azi), GO was observed up to the 4^th week, but a significant decrease in GO was noticed during 6-8^th week after the administration of Azi in 5^th week.

Conclusion: Azi is an effective drug in the remission of DIGO induced by combined therapy of CsA + Nf and thereby can be considered as a useful therapeutic regimen in minimizing the DIGO in transplant patients.