You'll need to use psoriasis drugs with some care. For example, a medicine called etanercept can trigger hypoglycemia (very low blood sugar). If your doctor thinks it's the best option to treat your psoriasis, you may need to change your diabetes medication. Another common psoriasis drug called methotrexate can cause serious liver damage in people with diabetes. If your doctor prescribes it, you'll need to have a blood test in a few months to make sure your liver's working the way it should.