The Journal of Phytopharmacology 2026; 15(2):192-195 DOI:10.31254/phyto.2026.15210

Research Article

Acute dermal toxicity evaluation of eugenol-incorporated hydrogel in Sprague Dawley rats

Pooja Krishna Kizhekku Veettil¹ , Suja Rani Satheesan² , Nisha Ayinikkattil Ravindran³ , Preethy John⁴ , Anoopraj Rajappan⁵ , Reji Varghese⁶

Pooja Krishna Kizhekku Veettil,Suja Rani Satheesan,Nisha Ayinikkattil Ravindran,Preethy John,Anoopraj Rajappan,Reji Varghese

1. MVSc Scholar, Department of Veterinary Pharmacology and Toxicology, College of Veterinary and Animal Sciences University, Mannuthy -680651, Kerala, India
2. Professor, Department of Veterinary Pharmacology and Toxicology, College of Veterinary and Animal Sciences University, Mannuthy - 680651, Kerala, India
3. Professor and Head, Department of Veterinary Pharmacology and Toxicology, College of Veterinary and Animal Sciences University, Mannuthy -680651, Kerala, India
4. Associate Professor, Department of Veterinary Pharmacology and Toxicology, College of Veterinary and Animal Sciences, Mannuthy, Thrissur- 680651, Kerala, India
5. Assistant Professor, Department of Veterinary Pathology, College of Veterinary and Animal Sciences University, Mannuthy - 680651, Kerala, India
6. Assistant Professor, Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences University, Mannuthy - 680651, Kerala, India

*Author to whom correspondence should be addressed.

Received: 6th February, 2026 / Accepted: 27th April, 2026 / Published : 8th May, 2026

Abstract

Background: Multidrug-resistant Staphylococcus aureus (MDRSA) infections significantly impair wound healing, often leading to chronic wounds and systemic complications. There is a need for wound dressings that are not only antibacterial but also biocompatible. Essential oils, such as eugenol, possess potent antibacterial properties, but their direct application is limited by volatility and instability. Incorporating eugenol into a polymeric hydrogel provides a stable delivery system, while ensuring safety prior to in vivo use is essential. Objectives: This study aimed to evaluate the dermal safety of eugenol-incorporated chitosan-PVA hydrogel (Eug-CH) in Sprague Dawley rats, following OECD Test Guideline 402. Materials and Methods: The inert chitosan-PVA hydrogel was synthesised via chemical crosslinking, followed by incorporation of eugenol as an emulsion. Acute dermal toxicity testing was conducted according to OECD 402, with topical application to the dorsal skin under semi-occlusive conditions. Sequential doses up to 2000 mg/kg were administered, with a total of five female rats used. Animals were monitored intensively for 24 h post-application and daily for 14 days, assessing dermal integrity, behaviour and systemic signs of toxicity. Results:  Topical application of Eug-CH produced no mortality or toxicity at doses up to the tested limit dose of 2000 mg/kg. Observations over 14 days revealed no adverse effects, including erythema, edema, tremors, convulsions, or behavioural abnormalities. Gross necropsy showed no organ abnormalities and a normal increase in body weight was noted. These findings indicate that the Eug-CH formulation is safe for dermal application in rats even upto the limit dose level. Conclusion: The Eug-CH hydrogel showed no mortality, skin irritation or pathological changes at doses ranging from 200 to 2000 mg/kg, with normal body weight gain observed over 14 days. With an LD?? exceeding 2000 mg/kg, the formulation is classified as GHS Category 5 (low hazard), confirming its safety for regulatory purposes. These results indicate that the eugenol incorporated hydrogel is highly biocompatible and suitable as an antibacterial wound dressing without risk of dermal toxicity.