TNF and Arthritis: Another study illustrated that the transcutaneous delivery of CBD via gel (0.6, 3.1, 6.2 or 62.3 mg/day) administered four consecutive days onto the skin resulted in a significant reduction of proinflammatory markers (CGRP, OX42 and TNFα) joint swelling and immune infiltration in a rat model of Arthritis and thickening of the synovial membrane in a rat model of Arthritis without psychoactive side-effects.