I always have Banamine on hand but you have to get it from your vet. It is an injection but if you know how to use it, it can save your horse's life. I believe it comes in a paste as well.
Benadryl is another thing I keep on hand, in capsule form.
Non-stick gauze pads
Betadine Scrub (Iodine, for washing)
Betadine Solution (Iodine, for soaking)*
Triple Antibiotic (Neosporin)
Bute (Must be purchased from Vet)
Mortar and Pestle/Pill Crusher
Stiff Plastic Grooming Brush
Small Rubber Soaking Bucket
Duct Tape (is amazing)
Clean Stainless Steel Hoof knife
A jug of purified or distilled water
Spray bottle of purified or distilled water
Sterile hypodermic needles and syringes.
IV bags (empty) I cute the tops off and use it for the white lightning if I don't have a bag.
Corona wound ointment