Gingivitis is a more common and reversible periodontal disease that mostly happens due to dental plaque build-up and such a periodontal disease is mostly treated using chemical mouthwashes like chlorhexidine, but despite its use in the prevention of the disease, the use of such type of mouthwashes is usually linked to several undesirable side effects. It was a multi-center randomized controlled clinical trial that assessed the safety and effectiveness of herbal mouthwash standardized to prevent gingivitis. Two hundred individuals who had mild to moderate gingivitis were selected in three dental care facilities and then randomly allocated into either the herbal mouthwash or control group to undergo 12 weeks of intervention. Clinical results were measured with the help of the Gingivar Index (GI) and the Plaque Index (PI) at baseline, 4, 8, and 12 weeks and the safety and tolerability measured with the structured adverse-event reporting. The findings showed statistically significant and progressive depressing effects of the herbal mouthwash group on both GI and PI scores relative to the control group at all intervals of the follow-up (p