Formulation and development of topical nano-emulgel TDDS for delivering Vitex Negundo as a painkiller: Enhancing effectiveness with natural essential oil permeation promoters in an innovative drug delivery system for rheumatoid arthritis treatment—A

Vitex negundo is a powerful herbal anti-inflammatory with effects similar to those of non-steroidal anti-inflammatory drugs (NSAIDs), which are commonly used to treat rheumatoid arthritis. Despite its benefits, Vitex negundo shares some drawbacks with NSAIDs, including gastrointestinal side effects such as vomiting and poor transdermal penetration, which limits its effectiveness in transdermal and gastrointestinal drug delivery. This study aimed to enhance the bioavailability of Vitex negundo by developing nano-emulgel with reduced particle size and to assess their effectiveness in treating rheumatoid arthritis. The researchers utilised a modified emulsification-diffusion method to create nanosized dispersions of Vitex negundo, incorporating hydroxypropyl methylcellulose (HPMC) as a gelling agent. Essential oils were also included to improve skin penetration by interacting with the stratum corneum (SC), thus enhancing the absorption of both lipophilic and hydrophilic drugs. The prepared Vitex negundo nano-emulgel were evaluated for various parameters, including rheology, particle size, drug content, drug release percentage, and in-vitro diffusion. The results indicated favourable properties: the particle size was 120.10 nm, the zeta potential was ± 30 mV, drug content was 99.50%, drug release percentage was 98.92%, and drug diffusion was approximately 98%. The formulation also had a pH of 6.8 ± 0.1. Overall, the Vitex negundo nano-emulgel, formulated with HPMC and eucalyptus oil as a permeation enhancer, demonstrated potential as an effective topical treatment for oedema and rheumatoid arthritis. “The study illustrates the formulation process of a drug blended with a polymer matrix. The drug is uniformly dispersed within the polymer matrix through high-shear mixing, ensuring optimal integration and consistency in the final product. The process involves high-shear blending to achieve a homogenous mixture, enhancing the drug’s stability and release characteristics within the polymer matrix.”