Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Intra-Muscular Injection Site Reaction


Intra-muscular injection of any medication causes some degree of inflammation. In some cases, that can be severe and cause visible swelling and pain.

Some medications are considered more irritating to the tissues and more likely to cause injection site problems. The incidence is also related to the injection technique used. Rarely, severe and life threatening bacterial infection can arise at the injection site.

my vet's role


Generally, good for most injection site reactions. However, complications such as abscesses can occur.

Clostridial infections can be life-threatening and result in widespread muscle and tissue damage and loss.

my role


I might observe

You might make these observations when a horse has this condition.

Very Common
Less Common
more observations

Questions To Ask Your Vet:
  • Should I expect a similar reaction to injection in the future?

Ideally, your vet should perform the intra-muscular injections on your horse.

If you give your horse intra-muscular injections, it is important to use proper injection technique, to only use appropriate medications prescribed by your vet, and to handle the medications properly from receipt, storage and injection.

further reading & resources

Author: Doug Thal DVM Dipl. ABVP