Synergistic Anti-Inflammatory Effects of Nigella Sativa-Mediated Colchicine Nanoemulgel in Gouty Inflammation: Dermal Delivery and Pharmacodynamics Assessment

Oral colchicine is associated with gastrointestinal adverse effects and limited therapeutic tolerability. This study aimed to develop a colchicine- Nigella sativa oil-loaded nanoemulgel and evaluate its dermal permeation and anti-inflammatory efficacy.

Formulation of a nanoemulgel based on colchicine (2% w/w) and N. sativa oil (8% w/w) was done via the spontaneous emulsification method. Stability of the formulation, globule size, drug and excipient interactions, and skin permeation studies were assessed. The anti-inflammatory activity of the formulation was assessed via the carrageenan-induced paw edema model in which 36 rats were used in six different groups.

The optimized nanoemulgel formulation showed a globule size of 152.6 ± 3.1 nm, and its stability was observed up to 3 months. In the case of the formulation, there was a remarkable reduction in paw oedema to 28.6 ± 1.9% at 4 hours ( p < 0.001), showing a 71.4% anti-edema effect. The values of cumulative permeation, flux, apparent permeability coefficient, and skin deposition were 62.9 µg/cm ² , 2.53 µg/cm ² /h, 3.76 × 10 ⁻⁵ cm/s, and 28.7 µg/cm ² , respectively.

The enhanced anti-inflammatory activity and dermal penetration indicate synergistic effects in the action of colchicine and N. sativa oil, indicating the therapeutic potential of this drug combination.

The colchicine- N. sativa nanoemulgel demonstrated enhanced dermal delivery and significant anti-inflammatory activity in an experimental rat model. Further investigations are required to establish clinical efficacy and safety.