A phase 1 clinical trial was performed in 16 healthy volunteers to primarily investigate safety of Portulaca grandiflora (P. grandiflora) as well as to preliminarily assess its efficacy on the immune system. The volunteers received 500 mg/day of P. grandiflora aqueous extract (250 mg capsule twice daily) for 2 months. No major side effects were reported from any of the subjects throughout the study. It was found that some significant changes in biochemical parameters were within normal limits. Hematological and immunological parameters were not altered after oral administration of P. grandiflora. Our results indicated that the P. grandiflora aqueous extract at the dose of 500 mg/day given to normal volunteers for 2 months was safe.
