Vahideh Ghorani - Pharmaciutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Marzieh Boskabady - Dental Materials Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
Mohammad Hossein Boskabady - Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran|Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
aida ansari - Allergy Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.

Objective: This is the first study to evaluate the effect of carvacrol on pulmonary function tests (PFT), and total and differential white blood cell (WBC) counts in healthy volunteers. Materials and Methods: Thirty healthy volunteers were recruited based on the inclusion and exclusion criteria. The subjects were treated with two doses of carvacrol (1 and 2 mg/kg/day) for 1 month. Total and differential WBC counts and PFT were examined before and after the treatment period. Results: There were no statistically significant differences in terms of total and differential WBC counts between pre and post-treatment with the two doses of carvacrol. Also, results of PFT tests indicated that administration of 1 mg/kg/day carvacrol had no effect on PFT parameters when comparing post-treatment values with pre-treatment values. Treatment with 2 mg/kg/day carvacrol for 1 month increased forced expiratory volume in first second (FEV1) (p<0.05). However, the changes in total and differential WBC counts as well as PFT values after 1-month treatment were not significantly different between two groups. Conclusion: The results of this study indicated that treatment of healthy individuals with 1 and 2 mg/kg carvacrol for 1 month has no negative effects on total and differential WBC counts nor PFT values.

Carvacrol, Pulmonary function tests, White blood cells, Healthy volunteers