yes you can get bute in tablet for if i am right. my dog got them a few years ago not sure about dosage for horses tho but you can getr it in a paste or try danilon as this is more palitable
I use a large oral syringe, put about 3 cm's of water in it and then put the sachet of bute in, shake it up and a bit and syringe it into the mouth that way. With so little water it coats the tongue and doesn't drip out. Works v.well.
My horse won't eat it either but tolerates me syringing it in.
I used to get tablets that were presecribed for dogs, as my old horse was the same. 5 tablets were equivalent to a sachet of bute. I don't think they were licenced for horses, but it is probably worth talking to your vet.