A person should call their doctor if they keep experiencing a faster or slower pulse. The doctor might recommend using a pacemaker to regulate the heart rate and prevent any heart-related disease. Also, a patient should see their doctor if they are taking medicine that causes them to faintness. The doctor might change the prescription to reduce fainting since it will help regulate the heart rate and improve the heart’s functions of supplying oxygen and nutrients. Also, a patient should reach out to the doctor about their heart rate if they feel light-headedness or dizzy, have trouble breathing or shortness of breath, or have pressure or pain in their chest.