Sometimes differences in brain chemistry can affect mood and cause depression. Sometimes people become depressed for no clear reason. Depression is sometimes linked to prescription drugs or certain illnesses. Some medications used to treat arthritis, heart problems, high blood pressure, or cancer can cause depression as a side effect. These side effects may not happen right away.
Scientists also think some illnesses can cause depression.
These include Parkinson's disease, stroke, and hormonal disorders. Genetics, too, can play a role. Studies show that depression may run in families. Children of depressed parents may be at a higher risk. Treatment Depression can be treated successfully.