boxer in trouble
hi, i have a 6-8 year old adopted boxer, jake. we took him from a family who had left him at their farm in the care of a watchman, because they migrated to the u.s. we never met the previous owners and do not know much about his earlier life. we guess he's about 7 years old, and got him 2 and a half years back. he got a dose of drontal plus, dewormer, a month back. 3 tabs, each for a dog of about 12 kgs. jake is 30 kgs. he has never been given more than a single tablet earlier. after 14 days, the vet advised a repeat dose. after 10 days, my dog started to have falling down spells. he would just start panting slightly and fall. he would get up in about 2-3 mins. appetite was normal. after 2 days, he was diagnosed with a kidney infection. total loss of appetite, severe depression. he was treated for this and the falls stopped, he was better. now it's been a week, but he is still depressed, does not eat any solid food, is very weak, and has had a bit of diarrhoea. please help. we're very attached to him, and i don't want him to suffer. fits and epilepsy have been ruled out.