What should I do about my Lhasa Apso's aggressive behavior?

I have a 7 year old male Lhasa Apso who is EXTREMELY aggressive. He growls every time you pick him up or touch him and he tries to bite if you try to give him medicine, put drops in his ears etc...I'm at the end of my rope. I don't know what to do with him anymore. He doesn't listen and he really seems to hate me. I would hate to bring him to the Humane Society because I don't want him to be put down but I am running out of options.