Heart Disease Home > Metoprolol Warnings and Precautions
- Are allergic to metoprolol, Lopressor, Toprol-XL, other beta blockers, or any inactive component used to make the medication. Your healthcare provider or pharmacist has a list of inactive ingredients.
- Have a slow heartbeat (less than 45 beats a minute).
- Have certain types of irregular heart rhythms (specifically second- or third-degree heart block).
- Have serious congestive heart failure.
- Have sick sinus syndrome.