This study investigated the cutaneous antinociceptive effects of tyramine and octopamine and their respective interactions with co-injection of lidocaine and compared them with noradrenaline. Cutaneous antinociceptive effects in rats was assessed through the blockage of cutaneous trunci muscle reflexes induced by needle pinpricks. Isobolographic analysis was used to assess the interaction between lidocaine and each drug. The results showed that at the ED75 (75% effective dose), tyramine and lidocaine caused 73% and 77% nociceptive blockade, respectively. The order of drug potency (ED50) is noradrenaline > lidocaine > octopamine > tyramine (p

Ching-Hsia Hung has completed his PhD at the age of 28 years from National Yang Ming Chiao Tung University, Taiwan. Ching-Hsia Hung was a professor in the Department of Physical Therapy at National Cheng Kung University in Taiwan. Her research interest is in the fields of exercise effect and physiology, pharmacology and systemic effect of analgesic agents, and pain science. She has published more than 100 papers in reputed journals and has been serving as an editorial board member of repute.