PRECAUTIONS: This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: heart rhythm problems (e.g., sick sinus syndrome or second-degree or third-degree AV block without a ventricular pacemaker, ventricular tachycardia, atrial flutter or fibrillation with Wolff-Parkinson-White or Lown-Ganong-Levine syndrome), severe low blood pressure, seriously compromised heart conditions (e.g., recent heart attack with lung congestion, cardiogenic shock). Before using this medication, tell your doctor or pharmacist your medical history, especially of: other heart problems (e.g., congestive heart failure, aortic stenosis, extreme bradycardia), kidney problems, liver problems, any allergies. This drug may make you dizzy; use caution engaging in activities requiring alertness such as driving or using machinery. Limit alcoholic beverages. To minimize dizziness and lightheadedness, get up slowly when rising from a seated or lying position. Caution is advised when using this drug in the elderly because they may be more sensitive to its side effects. This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. This medication passes into breast milk. Breast-feeding is not recommended while using this drug.

DRUG INTERACTIONS: Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription products you may use, especially of: amiodarone, benzodiazepines (e.g., midazolam, triazolam), beta-blockers (including eye drops), buspirone, carbamazepine, cholesterol-lowering "statin" drugs (e.g., lovastatin, simvastatin), cilostazol, cimetidine, cyclosporine, digoxin, general surgery anesthesia, intravenous (IV) calcium, other medications for high blood pressure or other heart conditions, quinidine, rifamycins (e.g., rifampin), St. John's wort. Check the labels on all your medicines (e.g., cough-and-cold products, diet aids) because they may contain ingredients that could increase your heart rate or blood pressure. Ask your pharmacist about the safe use of those products. Do not start or stop any medicine without doctor or pharmacist approval.