Can worming your horse cause colic?
Yes, worming your horse can bring on colic however this typically only happens if the horse has a high worm burden to start with and/or hasn’t been wormed in a while.
Colic attacks bought on after worming usually happen within 12 hours of being wormed. It is normally due to a high number of roundworms and/or tapeworms being present and then killed by the wormer. Giving a horse a wormer causes the worms to die wherever they reside within the horse’s digestive tract. If there is a high worm burden the worms can die and sometimes cause a blockage in the intestines or caecam of the horse, resulting in an impaction colic. Gas colic can also occur when the worms die and release gases which causes irritation and pain in the horse.
The risk of your horse colicking post wormer is far less than the potential health implications caused by worms. This is why it is always best to maintain a regular worming program to reduce/eliminate worms and in turn alleviate a number of other possible health concerns and even colic caused by the presence of worms.
If you are concerned about worming your horse please speak to your veterinarian and they will be able to advise the best worming protocol for the horse. This may involve worming your horse for different worms at different stages to avoid an overload of dying worms and possibly reduce the risk of colic.