Before taking propranolol, tell your doctor or pharmacist if you are allergic to it; or if you have had a serious reaction to other beta blockers (such as metoprolol); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: breathing problems (such as asthma, bronchitis, emphysema), heart failure, certain types of heart rhythm problems (sinus bradycardia, Wolff-Parkinson-White syndrome, second- or third-degree atrioventricular block), overactive thyroid (hyperthyroidism), kidney disease, liver disease, blood circulation problems (such as Raynaud's disease), a certain adrenal gland tumor (pheochromocytoma), mental/mood disorders (such as depression), certain muscle/nerve disease (myasthenia gravis), severe allergic reactions.

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Liquid forms of this medication may contain alcohol. Caution is advised if you have alcohol dependence or liver disease. Ask your doctor or pharmacist about using this product safely.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

This product may prevent the fast/pounding heartbeat you would usually feel when your blood sugar level falls too low (hypoglycemia). The risk is higher if you have diabetes, or are vomiting, fasting, or not eating regularly. Other symptoms of low blood sugar level, such as dizziness and sweating, are not affected by this drug.

If you have diabetes, this product may make it harder to control your blood sugar levels. Check your blood sugar levels regularly as directed by your doctor. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination. Your doctor may need to adjust your diabetes medication, exercise program, or diet.

Children may be at greater risk for low blood sugar (hypoglycemia) while using this drug, especially if they are vomiting or not eating regularly. To help prevent low blood sugar, make sure children eat regularly. If your child cannot eat regularly, is vomiting, or has symptoms of low blood sugar (such as sweating, shaking), tell the doctor right away.

During pregnancy, this medication should be used only when clearly needed. Infants exposed to this medication during pregnancy may have low birth weight, low blood sugar, or slow breathing/heartbeat. Discuss the risks and benefits with your doctor.

This drug passes into breast milk. Consult your doctor before breastfeeding.