How Can Severe Anger And Anxiety Be Treated?

In seeking guidance and direction for how to approach primary doctor, what meds are best to treat a person who may not be depressed, but appear to be angry. My father-in-law is in poor health - he has an EF of 10 %. Only 2 people in the family have been exposed to outbursts of anger , while the rest of the family has not. I m thinking that my father-in-law could be experiencing anxiety. I have asked him how he feels about his health, his outlook, in general, and he denies depression. He offers an explanation as to why these 2 family members might feel his wrath , which is understood.