Evaluation of Safety Parameters of Ayurvedic Antimicrobial Formulation for Treatment of Vaginitis during Acute and Chronic Oral Toxicity and Vaginal Irritation Studies in Animal Models

Introduction: This in vivo preclinical toxicity study has been done to standardize a new vaginal herbal formulation consisting of dried parts of the stem barks of Azadirachta indica A. Juss. and Saraca asoca Roxb. who find mention in many Ayurvedic medicine texts for treatment of vaginitis. Both Acute and chronic toxicities of its hydro alcoholic (30:70) extract have been evaluated using the oral as well as vaginal route of administration through haematological and histopathological studies of the stomach, liver, and kidney. Vaginal irritation test has been also done to assess the redness, ulceration, bleeding, etc., during drug administration.

Materials and Methods: Acute toxicity study was carried out on Swiss albino female mice weighing about 20–30 g following OECD guidelines. A single dose of hydro-alcoholic extract of the research drug was administered orally at the level of 300, 500, 1000, 1500 & 2000 mg/kg to different groups and animals were observed for the appearance of toxic symptoms up to 24 hours.

During chronic toxicity study, three doses of hydro-alcoholic extract, namely the therapeutic dose 500 mg/kg, 2500 mg/kg (5 times the therapeutic dose) and 5000 mg/kg body weight (10 times the therapeutic dose) were prescribed orally for 90 days to the three experimental groups each having 6 female Wister rats to assess the toxic effect or mortality on daily observation basis. Toxic symptoms including muscle spasm, loss of righting reflex, tremors, behavioral changes, locomotion, convulsions, and mortality were noted along with body weight changes, food and water intake. The animals were sacrificed on the 90th day, and their haematological parameters and liver function test (LFT) were done. Histopathological studies were done on slides of dissected stomach, liver, and kidney and internal structures of cells, tissue, and mucous membrane, etc., were observed.

Vaginal irritation testing was performed on 18 female Wistar rats divided into 3 test groups, namely, control, drug-treated (500 mg/kg), and placebo-administered, using vaginal route of drug administration. Animals were necropsied 24 h after final vaginal dose and heart, kidney, liver, lung, ovary, pancreas, uterus, and vagina were excised, and histopathological examination of the internal structure of their cells, tissues, and glands was done.

Results and Discussions: The acute toxicity tests performed on the research formulation revealed no signs of behavioural changes up to the dose of 2000 mg/kg and no mortality was reported up to 24 hours.

During the chronic toxicity testing, no animal mortality was observed and no significant toxic effects were observed over a prolonged period. At the same time, the haematological studies, LFT and hormonal parameters of blood did not show any noticeable differences, and no significant damage of cells, tissues, epithelium lining, or other structures of stomach, liver, and kidney was observed during histopathological studies.

The vaginal irritation (subacute toxicity) studies indicated that no differences were observed among treatment groups in respect of haematological parameters as well as weight and internal structures of all vital organs during the histopathological examination.

Conclusion: The results clearly indicate the non-toxic attribute of research drug formulation on the basis of analysis of blood parameters and reproductive hormones using oral and intravaginal administration routes