When is a twitch effective and how do you properly use one?

A twitch is a restraint device that applies pressure to the horse's upper lip and has been used in horsemanship for centuries as a means of calming horses for procedures that would otherwise require sedation or multiple handlers. Its effectiveness is genuine and well-documented in horses for whom it works, and understanding both when it is appropriate and how to apply it correctly makes it a safer and more effective tool. The mechanism of the twitch is more complex than simple pain distraction. Research has found that correct application triggers the release of endorphins — the same pain-relieving neurochemicals that exercise produces — which creates the genuine calming effect and the characteristic drooping lower lip and lowered head carriage that a correctly applied twitch produces. This endorphin response is also why the effect diminishes if the twitch is left on too long — the response fades after several minutes and the horse becomes progressively more agitated rather than remaining calm. The appropriate situations for twitch use are procedures that are brief, specific, and genuinely necessary — clipping around the ears or face in a horse that resists, veterinary examination of a wound or an eye, injection at a location the horse objects to, nasogastric tube passage, and similar short-duration procedures where a calm horse is necessary for safety and accuracy. Application requires two people — one to hold the twitch and monitor the horse's response, one to perform the procedure. Grasp the upper lip firmly with one hand and slide the loop of the twitch over the lip and twist the handle until the rope is snug enough to apply firm pressure but not so tight that the lip is being crushed. A correctly applied twitch produces relaxation rather than increased agitation — if the horse becomes more agitated the twitch may not be appropriate for this individual. The twitch should be applied only immediately before the procedure begins and released immediately when finished. Some horses do not respond appropriately regardless of correct application — they become more agitated rather than calmer. A horse that escalates in response to the twitch should have it removed promptly and sedation requested from the veterinarian rather than attempting to maintain a twitch on a horse whose response indicates it is not working.