help us save gus!

gus is a 5 year old, sweet as pie english fox hound that was rescued in june and is living with his amazing foster family. he was diagnosed with epilepsy in june and placed on medication due to the severity of his episode. he was doing great until august when he had another episode. this has caused major concern for his vet and his family. they have done every test under the sun with no obvious results. they had an ultra sound and found that his spleen is enlarged, but blood tests gave no answers. he is fed a special diet and has been losing weight even though he eats like a beast. his beautiful hound black nose and lips have been losing color, an obvious sign that something is wrong. currently, his foster family has outstanding vets bills around $1,000 and will need to take poor gus to an internist and/or a neurologist. please, help us give gus a chance to enjoy his second chance at happiness.