On the side of my dad ankle is very swollen. by the looks of it its getting bad. i touch it and felt like the bones are swollen. no insect bite, its been four months now. what medications can he takes?

Diagnosis first: You first have to take him to the doctor to find out what the problem is. Once a diagnosis is made treatment will be a lot easier.

See a DPM: After 4 months of symptoms, there has to be an evaluation. Don't guess what it could be. Consider going to the podiatrist to have a comprehensive foot examination which will many times include an evaluation as well as x-rays. There's no harm in having it checked by the expert.