So you have a new medication to try, or are about to try one that was just approved by the FDA. Congrats!
You might be wondering if there are any interactions with other medications, and if so, which ones.
Propranolol (often abbreviated as “Propranol”) is a medication often used to treat high blood pressure, angina, and heart attacks. It is a β-blocker which works by relaxing the muscles in the walls of the blood vessels, thus decreasing blood pressure. In most cases, it is very effective in treating these conditions, and is considered one of the safest medications to use when treating cardiovascular disease.
Viagra is another medication used to treat cardiovascular disease, including high blood pressure and angina. It is a phosphodiesterase type 5 inhibitor which works by increasing blood flow to certain areas of the body. In most cases, it is very effective for these conditions as well (especially when used in combination with other medications), and is considered safe for use even when repeated doses are required.
The following table provides a list of drug interactions that have been reported for Propranolol and Viagra (also known as generic drugs in the U.S.). Some of the interactions are serious and require medical attention, while others are not as severe but may require close monitoring.
Note: This list contains drug interactions that have been reported in humans and in reputable scientific journals (i.e., Food & Drug Administration (FDA) AERS reports). There are many other interactions that have not been reported in the scientific literature, and these may vary by person, medication, and/or dose.
Serious Interactions
There have been a few reported cases of extreme allergic reactions and death from taking Propranolol with the following medications:
- amitriptyline
- atenolol
- ciprofloxacin
- enalapril
- erythromycin
- flecainide
- fluoxetine
- isotretinoin
- lasix
- methadone
- metoprolol
- nitrofurantoin
- oxybutynin
- pseudoephedrine
- triparanol
- vinyl acetate
- Warfarin
The above medications are indicated for treating various medical conditions, but have been shown to interact with Propranolol in a particularly harmful manner. Patients who are taking or who may be candidates for taking Propranolol should consult their physician before taking any medication that may interact with it. It is also advisable to consult a pharmacist or doctor if you become aware of any interactions not listed in this article.
Common Interactions
Many of the reported interactions below are rather serious in nature, and in some cases may require a dose adjustment or discontinuation of one or both of the medications in question. In almost all cases, the interactions become more severe if both drugs are taken together.
“Propranol” Interactions with Other Drugs
In the U.S., Propranol is available only as a generic drug. However, in other countries it may be available under a brand name. In any event, it is very likely that some of the medications and substances listed below will interact with Propranol.
Alcohol
As mentioned above, in most cases Propranol will not interact badly with other medications. However, in rare instances there have been reports of severe allergic reactions, including anaphylaxis from alcohol consumption when combined with Propranol. Therefore, it is advised by the FDA that alcohol and beta-blockers should not be taken together. Additionally, drinking alcohol while on Propranol increases the risk of side effects, including dizziness, weakness, and fainting. These side effects are more likely to occur when larger amounts of alcohol are consumed. Moreover, alcohol has been known to interact with various medications, including those used to treat cardiovascular disease. As a result, if patients are already allergic to alcohol or if it interferes with their medication regimens, then it might be best to avoid alcohol altogether while taking Propranol.
Amiodarone
Amiodarone is a medication often used to treat heart rhythm disorders and angina. It is an anti-arrhythmic agent that also has vasopressor and phosphodiesterase inhibitor properties. It is a highly effective medication for treating these conditions, but also has many dangerous interactions. Amiodarone is known to interact with various medications, including insulin, theophylline, cyclosporine, and Propranol. If patients are already taking or are candidates for taking amiodarone, then it might be best to avoid combining it with other medications or supplements that are not in direct competition with the drug (e.g., caffeine, xanthine products, or vitamin C).
Caffeine
Caffeine is one of the most common and most well-known stimulants. It is often found in energy drinks and is also present in coffee, tea, and various chocolate products. Due to its stimulating nature and widespread availability, caffeine is often a precursor to dangerous drug combinations. In combination with certain medications (e.g., amphetamines, ephedrines, and methylphenidate), it has been known to cause severe adverse effects, including cardiac arrest, heart failure, and death. Caffeine is also known to interact with various medications, including some used to treat cardiovascular disease. It has been shown to significantly decrease the effectiveness of the following drugs:
- atorvastatin
- betamethasone
- cimetidine
- indomethacin
- metoprolol
- oxytocin
- propranolol
- trimazosin
- Warfarin
Chlorpropamide
Chlorpropamide is a medication often used to treat diabetes, as well as to reduce cholesterol levels. It is a hypoglycemic agent that also inhibits the reabsorption of cholesterol in the kidneys. It has been shown to interact with several medications, including carbamazepine, diltiazem, verapamil, and nicotinic acid. If patients are already taking or are candidates for taking chlorpropamide, then it might be best to avoid combining it with other medications or supplements that are not in direct competition with the drug (e.g., caffeine, xanthine products, or vitamin C). In most cases, the interactions are either neutral or beneficial, but in a couple of rare instances they have been known to produce serious adverse effects. One of the most serious of these interactions occurs when chlorpropamide is taken with certain pain medications (e.g., amitriptyline or oxyphenbutazone). The combination of these substances has been known to cause liver toxicity, as well as significant decreases in blood pressure and heart rate. Therefore, if patients are already taking or are candidates for taking either of these medications, then it might be best to avoid combining them with chlorpropamide.
Digoxigenic Acid
Digoxigenic acid is a substance that occurs naturally in the human intestine. It is a metabolite of vitamin C that aids in the digestion of carbohydrates (i.e., sugar). Although it has not been shown to have any specific side effects, it is known to interact with various medications. The most significant of these interactions are with Propranol and Amiodarone. Patients who are taking or who may be candidates for taking Propranol should consult a physician before taking any medication that may interact with it, as well as avoid consuming alcohol while on this medication. Amiodarone patients should likewise consult a physician before combining this drug with any other medication or substance, due to its dangerous interactions. Although this combination has been known to cause serious side effects, including death, it has also been known to produce satisfactory results when used in specific cases. Therefore, it might be best to attempt to find the middle ground when administering this combination of medications.