How to Give your Horse an IM Shot

Everyone should know how to give an intra-muscular shot to their horse because there are times when it’s impractical (let alone too expensive) to have your vet come to your barn to come and give a series of injections for something such as a course of antibiotics.

Instructions

Giving an IM shot is relatively simple:

• Clean the area with alcohol (some sites say this isn’t necessary, but I don’t think it can hurt)
• Insert the needle deep into the muscle
• Attach the syringe
• Aspirate (pull back on the plunger to make sure you are in the muscle, not in a vein). Some medications can be harmful if incorrectly injected.
• Inject the medication slowly.
• Watch your horse for an adverse reaction.
• Dispose of the used needle and syringe properly.

Need something visual? Here’s an  illustrated guide and  another good resource.

This triangular area of the neck is one of the easiest places to give an IM injection.

The neck is the most common place to give shots. Use the area designated by the triangle.

Tips & Warnings

• If you need to give a series of IM shots consider rotating the injection sites. Giving all the sites in the neck, for example, can make your horse sore. Instead of just alternating sides, consider using the buttocks or pectoral muscles too.

While adverse reactions are infrequent, there are some risks to performing IM injections. These include:

• Dependent Oedema – a mild, cool swelling that can occur after IM injection into the chest muscles. It normally will resolve itself over time, but if the swollen area is warm, the horse seems to be in pain or is lethargic, it’s a good idea to call your vet.
• Abscesses and Bacterial Infections are associated with certain medications. The most common one is flunixin meglumine (Finadyne®). One of the most serious side effects of an intramuscular injection of this drug can be a bacterial infection involving Clostridium spp. This is a severe infection that requires veterinary care. Banamine is also associated with bad reactions when delivered through IM injection, and it is recommended that you do not inject it.
• Procaine Reaction – occurs as a reaction to procaine penicillin when the procaine gains access to the circulatory system and causes intense constriction of the blood vessels in the brain. It is very important that when you give this medication that it is not injected into a vein. If this reaction occurs, it manifests itself in ways that vary from muscle twitching to kicking, pawing, seizures, and even sudden death.