The effect of carvacrol on inflammatory mediators and respiratory symptoms in veterans exposed to sulfur mustard, a randomized, placebo-controlled trial.

The aim of this study was to evaluate the effect of carvacrol on serum level of inflammatory mediators and respiratory symptoms in the veterans exposed to sulfur mustard (SM).

Twenty-one patients who were exposed to SM more than two decades' ago were divided to placebo and carvacrol (1.2 mg/kg/day) treated groups. Serum levels of Tumor Necrosis Factor-α (TNF-α), Monocyte chemotactic protein-1 (MCP-1), Vascular endothelial growth factor (VEGF), Epidermal growth factor (EGF), forced expiratory volume-one second (FEV₁) and respiratory symptoms including; Chest wheeze (CW), night wheeze (NW), night cough (NC) and cough and wheeze during exercise (ECW) were assessed at the baseline (step 0), one and two months after starting treatment (step I and II, respectively).

FEV₁ value was significantly increased in carvacrol treated group in step II compared to step 0 (p < 0.001) and also increased in step II compared to step I (p < 0.05). The respiratory symptoms including; CW and NW was significant decreased in carvacrol treated group in step I and II compared to step 0 (p < 0.01 to p < 0.001), NC and ECW were significantly decreased only in step II compared to step 0 (p < 0.01, for both cases). The serum levels of TNF-α, EGF and VEGF were decrease in carvacrol treated group in step I and II compared to step 0 (p < 0.05 to p < 0.001). The serum level of MCP-1 was decrease in carvacrol treated group only in the step II compared to step 0 (p < 0.05).

Two months' treatment with carvacrol reduced inflammatory cytokine and chemokine while increased anti-inflammatory cytokines and improved respiratory symptom and FEV₁ value in SM exposed patients.

This trial was registered under IRCT2014031617020N1 at http://www.irct.ir/.