Stallions and Dewormer

Question
I have heard that certain dewormers can cause problems in breeding stallions.  I was just wondering what the cause of these problems are and they best way to avoid them.

Answer
Hi Cari,

The best way to avoid any potential problems with dewormers in either stallions or pregnant mares, is to read the label.

Dewormers that are safe for pregnant mares and stallions will state right on the box that they have been tested safe.  Although I have never seen one state that it is safe for stallions particularly.  If it will be safe for a pregnant mare, you can be assured it will be safe for a stallion.

I honestly have never seen a stallion have an adverse reaction, (related to breeding) from any type of dewormer.  You can get reactions out of any horse from deworming, which can include an allergic reaction, or a mild case of colic.

The best thing to do, is read the label and to use dewormers that you have used before that you know your horse has not had a reaction to.