Evaluation of changes in the haemoglobin of skin and muscle tissue of the calf, as induced by topical application of a nonivamide/nicoboxil cream.

Topical agents like nonivamide and nicoboxil induce hyperaemisation and increase cutaneous blood flow and temperature. This study aimed to determine the effects of a nonivamide-nicoboxil cream on haemodynamics in the skin and calf muscle, via optical spectroscopy, discriminating between the changes for skin and muscle. Optical spectroscopy was applied in the visible (VIS) and near-infrared (NIR) wavelength range. The study determined the effect of the cream on changes in oxygenated (ΔoxyHb) and deoxygenated (ΔdeoxyHb) haemoglobin in skin and muscle, as well as on tissue oxygen saturation (SO2) in the skin of 14 healthy subjects. The left and right calves of the subjects were either treated with nonivamide-nicoboxil cream or were sham-administered. NIR spectroscopy allows noninvasive in-vivo examination of the oxygenation of human skeletal muscle. Topical administration of the nonivamide-nicoboxil cream significantly increased the concentration of oxygenated haemoglobin and tissue oxygen saturation in the skin, as well as the concentration of oxygenated haemoglobin in the muscle of the treated legs after 15 min, but with stronger and faster effects in the skin. The topical application of the nonivamide-nicoboxil cream increased blood flow in (smaller vessels of) the skin and muscle tissues.