Can Medication For Bipolar Cause Large, Hard Lumps On Legs And Swollen Ankles?

Hi my husband is bipolar & he has put on a lot of weight even though he is working on the land doing very hard work in very hot weather & not eating very much. Coffee for breakfast, half to a full sandwidge for lunch & normal sized evening meal. He has very large hard lumps on the back of the top part of his legs, his feel & ancles are swelling up quite badly & the hair on the lower part of his legs are thing out a lot. Can this be from his meds.