Effect of Geraniol and Clarithromycin Combination against Gastric Ulcers Induced by Acetic Acid and Helicobacter pylori in Rats

Background: Previous work showed geraniol to have anti‑Helicobacter pylori activity in vivo and in vitro. Further, it has augmented the anti‑H. pylori activity of clarithromycin in vitro. Objective: Geraniol and clarithromycin combination was investigated for anti‑ulcer and anti‑H. pylori activity in rats. Materials and Methods: Ulcers were induced by injecting acetic acid into the subserosal layer of the stomach followed by intragastric inoculation of H. pylori for 7 days. Geraniol (30 mg/kg) and a drug combination (geraniol, 30 mg/kg and clarithromycin, 25 mg/kg) were administered twice daily for 14 days, and parameters were measured at the end of treatment. Results: Geraniol alone or in combination with clarithromycin significantly (P < 0.05) lowered the ulcer index and improved the curative ratio. Histopathological examination showed a significant reduction (P < 0.05) in the ulcer score in the geraniol and geraniol–clarithromycin treated animals compared with the ulcer controls. Both the treatment groups showed significant (P < 0.05) increase in the glutathione level and reduction in the malondialdehyde, interleukin 6, and tumor necrosis factor‑α level in the gastric mucosa compared to control group. Both produced a 50% reduction in the rapid urease test, which is further confirmed using modified Giemsa staining. Conclusion: Geraniol, alone or in combination with clarithromycin, showed a significant ulcer healing effect which was associated with anti‑H. pylori, anti‑inflammatory, and antioxidant effects in the gastric mucosa. However, the effects of the geraniol and clarithromycin combination were not significantly different from the effects of geraniol alone in this model.