You can purchase a ready-made pet first aid kit or assemble your own kit with the following items. Talk with your veterinarian to discuss additional items that might be useful for your pet.

Remember to check the contents of the kit periodically to replace any expired or depleted supplies.

The Canadian Veterinary Medical Association recommends that your pet first aid kit include:

• muzzle
• protective gloves
• digital/rectal thermometer
• rubbing alcohol
• lubricating jelly
• pen light
• blanket for pet transport
• Q-tips
• adhesive tape
• gauze squares
• gauze roll
• stretchy bandage
• no-stick sterile wound dressing
• hydrogen peroxide (3% strength)
• antibacterial soap
• sterile rinse solution (saline, used as a wound flush or eyewash)
• clean syringes (1 cc and 5 cc)
• cotton roll
• splinting item (e.g., a wooden coffee stir stick or tongue depressor can be used for small pets)
• bandage scissors
• tweezers
• first aid ointment or cream
• corn syrup

From: https://www.canadianveterinarians.net/documents/creating-a-first-aid-kit-for-your-pet