LACK OF LOCAL-ANESTHETIC EFFICACY OF SARAPIN(R) IN THE ABAXIAL SESAMOID BLOCK MODEL

Sarapin(R) is a distillate of the pitcher plant that has long been use d in human and veterinary medicine for 'regional analgesia'. The mecha nism of the reported analgesic response is unknown; however, the agent is purported to provide more effective analgesia for slow, chronic pa in than for sharp, acute pain. Reportedly, Sarapin(R) is also widely u sed as an analgesic agent in the horse, generally in combination with corticosteroids and other agents. To determine its local anaesthetic e fficacy in the horse, we tested Sarapin(R) in a unilateral abaxial ses amoid block model at two dose levels, 2 mL and 10 mL per site, respect ively. Cutaneous pain was induced with a light/heat lamp, and analgesi a was assessed by measuring the hoof-withdrawal reflex latency period. Neither dose of Sarapin(R) altered hoof-withdrawal reflex latency in this experimental model tested over a two-week period. Based on the de monstrated efficacy of this local anaesthetic model, it seems clear th at Sarapin(R) has no significant classical local anaesthetic actions i n the horse, and probably not in other species either.