What is propranolol used for?
LAST UPDATED: Dec 02, 2020
6 MIN READ
HERE'S WHAT WE'LL COVER
Originally developed to alleviate chest pain associated with heart disease, propranolol is mainly used to treat high blood pressure (hypertension), atrial fibrillation and migraine (Srinivasan, 2019). Propranolol, also found under the brand name Inderal, falls into a class of drugs called beta blockers, which help slow down your heart rate and reduce blood pressure by blocking certain hormones in the body (Shahrokhi, 2020).
What is propranolol?
Propranolol (brand name Inderal) is a prescription drug called a beta blocker. While we have control over a lot of things in our bodies, like how we move our arms and legs, how we chew and swallow, or when we go to the bathroom, there are certain things in our bodies that happen automatically (like how our heart beats or how our digestive system breaks down food).
These automatic processes have two main settings—the “on” setting, also called “fight or flight” increases our heart rate, and makes us more aware of our surroundings and getting us moving, while the “off” setting, also called “rest and digest,” slows down our heart rate and lets us relax (Waxenbaum, 2020).
So how does propranolol work? It blocks the “on” setting, reducing how hard our heart pumps. This is helpful for treating a range of conditions, including the chest pain associated with heart disease, rapid heartbeat associated with anxiety, and high blood pressure, among others (Shahrokhi, 2020).
High blood pressure
Almost half of all adults in the United States have high blood pressure (hypertension)—a major risk factor for developing heart attacks, heart failure, and even stroke (CDC, 2019). Propranolol treats hypertension by slowing down your heart rate, which in turn helps reduce blood pressure. It may be recommended on its own, or in combination with other treatments to reduce blood pressure.
Chest pain (angina pectoris)
Chest pain or discomfort caused by angina occurs when not enough blood is getting to the heart muscle, usually due to blockages or narrowing of the arteries (AHA, 2015). Propranolol works by reducing how hard the heart muscle works, thereby reducing the amount of oxygen the muscle needs. This improves chest pain and increases a person’s exercise tolerance (FDA, 2010).
Atrial fibrillation (afib) is a heart condition that causes an irregular heartbeat, also known as an arrhythmia (AHA, 2016). Left untreated, afib can lead to more serious problems like blood clots and heart failure. Beta-blockers like propranolol may be prescribed alongside other treatments to control irregular heart rhythms and prevent afib from reoccurring in certain patients (Dezsi, 2017).
Heart attack (myocardial infarction)
Heart disease is the leading cause of death in the United States. It’s also the main cause of myocardial infarction (another term for heart attack), which a person suffers roughly every 40 seconds in the U.S. (Virani, 2020). Propranolol is commonly recommended for patients who survive a heart attack to reduce the chance of death, and as well as keeping the heart stable.
While there is no cure for migraines, medications can help people get through migraine attacks or prevent them from happening in the first place. Propranolol reduces the severity and how often attacks occur, although the mechanism behind how it works isn’t fully understood yet.
Essential tremor is characterized by involuntary moving or shaking of the body that isn’t caused by another medical condition. It’s often hereditary and can affect the hands, arms, legs, vocal cords, and torso (NIH, 2020). Propranolol can be prescribed to decrease the visibility of tremors but doesn’t reduce the frequency. It isn’t used to treat tremors related to Parkinson’s disease.
Hypertrophic obstructive cardiomyopathy (HOCM)
HOCM is a hereditary condition that thickens the wall that divides between the left and right sides of the heart (Nishimura, 2017). This condition can lead to sudden death in younger adults. Beta-blockers are often used to stabilize heart rhythms and alleviate symptoms of HOCM like chest pain, shortness of breath, and dizziness.
A rare tumor that appears in the adrenal glands, pheochromocytoma may cause episodes of high blood pressure, heart palpitations, and excessive sweating (NORD, n.d.). High blood pressure is one of the most common symptoms, and it can be controlled with drugs like propranolol.
Because propranolol is so effective at reducing certain symptoms associated with anxiety — like sweating and rapid heartbeat — it is sometimes used for things like performance anxiety or stage fright. If you've ever experienced performance anxiety, you are very familiar with the symptoms: racing heart, clammy hands, feeling like you might throw up. To suppress symptoms like this before a public-speaking event or musical performance, for example, a healthcare provider may recommend taking a beta-blocker beforehand (Srinivasan, 2019).
Side effects of propranolol
Propranolol carries a black box FDA warning, which means it can have serious or life-threatening risks (FDA, 2010). Stopping this drug suddenly can lead to chest pain or even a heart attack—do not stop taking propranolol without speaking to a healthcare professional.
Here are some of the most common side effects of propranolol (DailyMed, 2019):
Dizziness or lightheadedness
Nausea, vomiting, and diarrhea
Changes in mood
Shortness of breath, wheezing, or a cough
Less common but more severe adverse reactions to propranolol include: low blood pressure (hypotension), decreases in blood sugar levels, severe allergic reactions, and bradycardia, which is when the heart rate drops too low resulting in dizziness, fainting, fatigue, and chest pain.
Propranolol can also mask symptoms of other health conditions. For example, it may mask signs of hypoglycemia (low blood sugar) in people who are diabetic; when blood sugar levels are too low for too long, seizures and even death can occur. Beta blockers may also mask symptoms of hyperthyroidism (when your body produces excess thyroid hormones), which can lead to thyroid storm, a condition where heart rate and blood pressure can skyrocket to deadly levels. Propranolol can also worsen other underlying conditions, including heart failure and lung disease (DailyMed, 2019).
Propranolol interacts with hundreds of medications, some mild and others severe. Here are some of the major drug interactions to be aware of (FDA, 2010):
Drugs affecting the cytochrome P-450 system: Propranolol is broken down in the liver by the P-450 system. When taken with other drugs that impact this system, propranolol levels in the body can be too high or too low. Examples of these medications include cimetidine, fluconazole, and fluoxetine (brand name Prozac; see Important Safety Information).
Antiarrhythmics: These drugs affect heart rhythm, and combined with propranolol, can raise the risk of side effects. Common antiarrhythmic drugs include amiodarone, digoxin, lidocaine, propafenone, and quinine.
Calcium channel blockers: Propranolol also increases the risk for side effects, like low blood pressure and slow heart rate, when taken at the same time as certain calcium channel blockers. Examples include diltiazem, nicardipine, nisoldipine, nifedipine, and verapamil.
Migraine medication: Propranolol raises concentration levels of the migraine medications zolmitriptan or rizatriptan if taken together.
Blood pressure drugs: The effects of medications used to lower blood pressure, such as alpha-blockers or angiotensin-converting enzyme (ACE) inhibitors, are enhanced when taken with propranolol, causing blood pressure to drop too far. Examples include doxazosin, enalapril, lisinopril, prazosin, and terazosin.
Theophylline: This drug is known as a bronchodilator, which is used to treat lung issues like asthma. If taken with propranolol, the effects of theophylline may be reduced.
Diazepam: Available under the brand name Valium, diazepam is used to relieve symptoms of anxiety. Propranolol increases levels of diazepam in the body, which also increases the risk of side effects.
High cholesterol medication: Certain cholesterol medications can lower levels of propranolol in the body, and vice versa.
Monoamine oxidase inhibitors (MAOIs): This group of drugs is used for treating depression and other conditions. Taking MAOIs with propranolol could raise the risk of side effects. Types of MAOIs are isocarboxazid, phenelzine, selegiline, and tranylcypromine.
Warfarin: Warfarin is a medication that prevents blood clots from forming. When combined with propranolol, the levels of warfarin may increase in the body and increase your chance of bleeding.
Non-steroidal anti-inflammatory drugs (NSAIDs): NSAIDs help with pain and inflammation. However, they can decrease the effectiveness of propranolol; examples of NSAIDs include naproxen and ibuprofen.
Alcohol: Drinking alcohol while taking propranolol can raise the risk for side effects, such as dizziness and fatigue.
This doesn’t include the whole list of drugs that can interact with propranolol. Tell your healthcare provider about any medications you are taking before starting treatment with propranolol.
Propranolol comes in immediate and extended-release oral tablets, as well as an intravenous injection formula, or in a liquid form for those who have trouble swallowing pills. It comes in dosages of 10 mg, 20 mg, 40 mg, 60 mg, and 80 mg. The extended-release version can be found in higher doses of 120 mg and 160 mg. Dosages will vary depending on what it’s prescribed for. Extended-release propranolol is taken once daily, and the immediate-release version can be taken 2-4 times per day. Propranolol is only available with a prescription and costs anywhere from $9–$33 for a 30-day supply (GoodRX, n.d.).
Who should not take propranolol
There are certain groups of people who should use caution while taking propranolol, and there are others who should not take it at all. Propranolol can worsen conditions—including heart failure, liver disease, myasthenia gravis (a disorder that causes muscle weakness), kidney disease, and circulation-related diseases, such as peripheral vascular disease or Raynaud's disease—and should be taken with caution (FDA, 2010).
Other at-risk groups include people living with diabetes, bradycardia (slow heart rate), and low blood pressure. People with lung conditions like asthma, emphysema, or chronic obstructive pulmonary disease (COPD) should avoid taking this drug. There isn’t enough research yet on whether propranolol is safe for women who are pregnant. If you are nursing, consult with your healthcare provider before using this medication as it has been found to reach breastmilk (FDA, 2010).
If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
American Heart Association (AHA). (2015). Angina (Chest Pain). Retrieved Oct. 20, 2020 from https://www.heart.org/en/health-topics/heart-attack/angina-chest-pain
American Heart Association (AHA). (2020). Cardiac Medications. Retrieved Oct. 20, 2020 from https://www.heart.org/en/health-topics/heart-attack/treatment-of-a-heart-attack/cardiac-medications#beta
American Heart Association (AHA). (2016). What is Atrial Fibrillation. Retrieved Oct. 20, 2020 from https://www.heart.org/en/health-topics/heart-attack/angina-chest-pain
Centers for Disease Control and Prevention (CDC). (2020). Estimated Hypertension Prevalence, Treatment, and Control Among U.S. Adults. Retrieved on Oct. 21, 2020 from https://millionhearts.hhs.gov/data-reports/hypertension-prevalence.html
DailyMed. (2019). Propranolol hydrochloride capsule. Retrieved Oct. 20, 2020 from https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8efc9fc6-6db0-43c9-892b-7423a9ba679f
Dezsi, C. A. & Szentes, V. (2017). The Real Role of β-Blockers in Daily Cardiovascular Therapy. American Journal of Cardiovascular Drugs, 17 (5), 361-373. doi: 10.1007/s40256-017-0221-8. Retrieved from https://link.springer.com/article/10.1007%2Fs40256-017-0221-8
National Institute of Neurological Disorders. (2020). Tremor Fact Sheet. Retrieved on Oct. 22, 2020 from https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Tremor-Fact-Sheet
National Organization for Rare Disorders (NORD). (n.d.). Pheochromocytoma. Retrieved on Oct. 22, 2020 from https://rarediseases.org/rare-diseases/pheochromocytoma/
Nishimura, R. A., Seggewiss, H., & Schaff, H. V. (2017). Hypertrophic Obstructive Cardiomyopathy. Circulation Research, 121, 771-783. https://doi.org/10.1161/CIRCRESAHA.116.309348. Retrieved from https://www.ahajournals.org/doi/10.1161/CIRCRESAHA.116.309348
Shahrokhi, M. & Gupta, V. [Updated 2020 Oct 5]. Propranolol. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan. Retrieved Dec. 4, 2020 from https://www.ncbi.nlm.nih.gov/books/NBK557801/
Srinivasan, A. V. (2019). Propranolol: A 50-Year Perspective. Annals of Indian Academy of Neurology, 22 (1), 21-26. https://dx.doi.org/10.4103%2Faian.AIAN_201_18. Retrieved from https://www.annalsofian.org/article.asp?issn=0972-2327;year=2019;volume=22;issue=1;spage=21;epage=26;aulast=Srinivasan
U. S. Food and Drug Administration (FDA). (2010). Inderal (propranolol hydrochloride) tablets. Retrieved on Oct. 20, 2020 from https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/016418s080,016762s017,017683s008lbl.pdf
Virani, S. S., Alonso, A., Benjamin, E. J., Bittencourt, M. S., Callaway, C. W., Carson, A. P., et al. (2020). Heart Disease and Stroke Statistics—2020 Update: A Report From the American Heart Association. Circulation, 141, 139-596. https://doi.org/10.1161/CIR.0000000000000757. Retrieved from https://www.ahajournals.org/doi/10.1161/CIR.0000000000000757
Waxenbaum, J. A., Reddy, V., & Varacallo, M. [Updated 2020 Aug 10]. Anatomy, Autonomic Nervous System. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan. Retrieved Dec. 4, 2020 from https://www.ncbi.nlm.nih.gov/books/NBK539845/