Yes. The risks associated with taking metoprolol increase in the presence of the following conditions: angina, hypertension, congestive heart failure, severe blood vessel or circulation problems, heart block, slow heartbeat, sick sinus syndrome, pheochromocytoma, lung diseases, diabetes, depression, liver or kidney diseases, thyroid disorders, or low blood sugar. People with diabetes or thyroid conditions may be less able to notice telltale signs of impending medical problems, such as low blood sugar or overactive thyroid. Both may be indicated by a faster heartbeat, and metoprolol succinate can mask that symptom. Additionally, this medication can impair your thinking and affect your ability to stay alert and operate machines or vehicles. There are a number of medications that can interact with metoprolol, so the doctor needs to know about all of the medications being taken. Women who are pregnant, planning on becoming pregnant or breastfeeding might put their child at risk if they take metoprolol. Stopping metoprolol too suddenly may increase the risk of heart attack, even if with no pre-existing heart condition. Before any sort of surgery, including dental procedures, the doctor needs to know about metoprolol use.