What is the side effect of Inderal?

If you have certain heart conditions or headaches, your doctor might suggest Inderal LA or Inderal XL as a treatment option for you. Inderal LA and Inderal XL are prescription drugs used to lower high blood pressure in adults. Inderal LA is also approved for the following uses in adults:

• prevention of migraine headaches
• treatment of hypertrophic subaortic stenosis (a heart condition that affects blood flow through your heart)
• treatment of stable angina due to atherosclerosis

The active ingredient in Inderal LA and Inderal XL is propranolol. (An active ingredient is what makes a drug work.) Inderal LA and Inderal XL are available as capsules that you swallow.

If you and your doctor decide that Inderal LA or Inderal XL are safe and effective for you, you’ll likely take the drug long term.

For more information about Inderal LA and Inderal XL, including details about their uses, see this in-depth article.

Like other drugs, Inderal LA and Inderal XL can cause mild to serious side effects. Keep reading to learn more.

Some people may experience mild to serious side effects during their Inderal LA or Inderal XL treatment. Examples of commonly reported side effects of these drugs include:

• fatigue (low energy)
• constipation
• dizziness*

* To learn more about this side effect, see the “Side effects explained” section below.

It’s possible you may have mild side effects while taking Inderal LA or Inderal XL. Examples that have been reported with these drugs include:

• belly cramping
• constipation
• decreased blood pressure
• diarrhea
• fatigue (low energy)
• impotence
• nausea and vomiting
• problems with sleep
• short-term memory problems
• cold hands or feet*
• dizziness*
• slowed heart rate*
• mild allergic reaction*

* To learn more about this side effect, see the “Side effects explained” section below.

In many cases, these side effects should be temporary. And some may be managed. But if you have symptoms that are ongoing or bother you, talk with your doctor or pharmacist. And do not stop taking Inderal LA or Inderal XL unless your doctor recommends it.

This list does not include all possible side effects associated with Inderal LA or Inderal XL. See the prescribing information for Inderal LA and Inderal XL for details.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Inderal LA or Inderal XL, visit MedWatch.

It’s possible that Inderal LA and Inderal XL may cause serious side effects. These include:

• congestive heart failure
• very low blood pressure
• nonallergic bronchospasm
• hypoglycemia (low blood sugar)
• Stevens-Johnson syndrome*
• very slow heart rate*
• severe allergic reaction†

This list does not include all possible side effects associated with Inderal LA or Inderal XL. See the prescribing information for Inderal LA and Inderal XL for details.

If you develop serious side effects while taking Inderal LA or Inderal XL, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after taking Inderal LA or Inderal XL. But it’s not clear whether this side effect occurred in studies.

Below are answers to some frequently asked questions about Inderal LA and Inderal XL’s side effects.

Does Inderal LA or Inderal XL cause weight gain?

Weight gain was not reported as a side effect in studies of people taking Inderal LA or Inderal XL. But weight gain can be a symptom of heart problems, such as congestive heart failure. This is a serious side effect of Inderal LA and Inderal XL.

With congestive heart failure, you may have increased fluid in your body. This can cause weight gain.

Talk with your doctor if you notice sudden or unexpected weight gain. They’ll try to determine the cause and help you find ways to treat it.

Is hair loss a side effect of Inderal LA or Inderal XL?

Hair loss was a side effect reported in studies of people taking Inderal LA or Inderal XL. But some people taking these drugs reported hair loss after the medications were approved by the FDA. It’s not clear whether this was a common or rare side effect.

Talk with your doctor if you’re concerned about hair loss with Inderal LA or Inderal XL.

Are Inderal LA’s side effects the same whether it’s used for migraine or other conditions?

Yes, side effects reported by people taking Inderal LA were the same for all conditions Inderal LA is approved to treat.

But keep in mind that Inderal LA can be used to lower blood pressure in people with high blood pressure. If you don’t have high blood pressure and take Inderal LA to prevent migraine episodes, you may have an increased risk of low blood pressure from this drug.

Symptoms of low blood pressure can include:

• dizziness
• fainting
• blurry vision
• fatigue (low energy)

Let your doctor know right away if you experience any of these symptoms. They’ll determine the cause of your symptoms and decide whether it’s safe for you to continue taking Inderal LA.

Learn more about some of the side effects Inderal LA and Inderal XL may cause.

Severe skin reactions, such as Stevens-Johnson Syndrome

Severe skin reactions, including Stevens-Johnson syndrome, have happened in people taking Inderal LA or Inderal XL. Stevens-Johnson syndrome is a rare, life threatening skin condition that begins with a rash and can progress to severe blistering. Early symptoms can be mild and resemble flu symptoms. They can include:

• fever
• body aches
• cough
• sore throat

After 1 to 3 days, symptoms may become more severe. They can include:

• spreading red or purple rash
• pain all over the skin
• pain in your eyes
• trouble swallowing
• blistering on your skin, mouth, nose, eyes, or genitals
• shedding of your skin

What might help

Seek emergency medical attention immediately if you have symptoms of Stevens-Johnson syndrome. You’ll likely need to go to a hospital to treat this condition.

If your doctor determines you have Stevens-Johnson syndrome, they’ll likely have you stop taking Inderal LA or Inderal XL. They’ll provide any wound care you need and check your skin for signs of infection. If necessary, they may prescribe antibiotics for skin infection. They may also prescribe medication to relieve your pain.

Cold hands or feet

Some people taking Inderal LA or Inderal XL have reported cold hands or feet. This side effect was reported after these drugs were approved by the FDA. It’s not clear whether this was reported during studies of Inderal LA and Inderal XL as well.

Cold hands and feet or fingers and toes can happen because of decreased blood flow to these areas. In rare cases, Inderal LA and Inderal XL can cause numbness in the hands and feet.

What might help

Mild symptoms can be relieved by gently massaging your hands or feet or placing them under warm running water. Avoid wearing a tight watch or tight jewelry on your wrists or ankles. They can decrease blood circulation to your extremities and worsen your condition.

Talk with your doctor if you have severe symptoms, such as numbness or pain in your extremities. They’ll determine whether it’s safe for you to continue taking Inderal LA or Inderal XL.

Dizziness

Beta-blockers, including Inderal LA and Inderal XL, can cause dizziness. This was a common side effect reported in studies of Inderal LA and Inderal XL.

Dizziness caused by beta-blockers can be a symptom of orthostatic hypotension. This is a sudden drop in blood pressure as you sit up or stand up. Orthostatic hypotension is more common when you first start taking medication to lower blood pressure. It usually goes away on its own as your body gets used to the drug.

Symptoms of orthostatic hypotension can include:

• dizziness or lightheadedness, especially when you sit up or stand up
• nausea
• blurred vision

What might help

If you feel dizzy, sit down for a moment. Dizziness caused by Inderal LA or Inderal XL usually goes away when you sit or lie down. If you lie down due to dizziness, try to keep your head elevated.

Avoid driving or riding a bicycle until you feel better. Also, avoid consuming alcohol, which can worsen dizziness.

To prevent dizziness from recurring, try to sit or stand up slowly. When rising from your bed, sit up slowly first. Wait a few minutes, then hold on to something sturdy as you stand. Talk with your doctor if you have recurring or worsening dizziness. They’ll determine whether it’s safe for you to continue taking Inderal LA or Inderal XL.

Slowed heart rate

Slowed heart rate is a common side effect reported in studies of Inderal LA and Inderal XL. Symptoms of this side effect can include:

• confusion
• dizziness
• fainting
• fatigue (low energy)
• shortness of breath

In rare cases, a slowed heart rate can lead to serious heart complications.

What might help

Talk with your doctor if you have symptoms of slowed heart rate. They’ll likely monitor your heart rate while you’re taking Inderal LA or Inderal XL. If your heart rate remains too slow, they may lower your Inderal dosage or recommend a different treatment.

It’s important to tell your doctor all the medications you take. Some of the medications may also slow your heart rate. Taking them along with Inderal LA or Inderal XL may slow your heart rate even more and increase your risk of serious complications. Your doctor will decide whether taking Inderal LA or Inderal XL is safe for you. They may adjust your dosage or discuss other treatment options with you.

Allergic reaction

Like most drugs, Inderal LA and Inderal XL can cause an allergic reaction in some people. But it’s not clear whether this side effect occurred in studies.

Symptoms can be mild to serious and can include:

• skin rash
• itchiness
• flushing (temporary warmth, redness, or deepening of skin color)
• swelling under your skin, usually in your eyelids, lips, hands, or feet
• swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms. Examples include:

• an antihistamine you take by mouth, such as Benadryl (diphenhydramine)
• a product you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Inderal LA or Inderal XL, they’ll decide whether you should continue taking it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Inderal LA or Inderal XL, they may have you switch to a different treatment.

Keeping track of side effects

During your Inderal LA or Inderal XL treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include factors such as:

• what dose of the drug you were taking when you had the side effect
• how soon you had the side effect after starting that dose
• what your symptoms were
• how it affected your daily activities
• what other medications you were taking
• any other information you feel is important

Keeping notes and sharing them with your doctor will help them learn more about how Inderal LA or Inderal XL affects you. They can then use this information to adjust your treatment plan if needed.

Inderal LA or Inderal XL may not be right for you if you have certain medical conditions. (This is known as a drug-condition interaction.) Other factors may also affect whether Inderal LA or Inderal XL is a good treatment option for you.

Talk with your doctor about your health history before starting either of these drugs. Below are some factors to consider.

Angina. Chest pain called angina can worsen if you suddenly stop taking Inderal LA or Inderal XL. In rare cases, this has led to heart attack. Due to this risk, your doctor will gradually decrease your dose if they determine you need to stop taking Inderal LA or Inderal XL. You should not stop taking either of these medications without first talking with your doctor if you have angina.

Allergic reaction. If you’ve had an allergic reaction to Inderal LA or Inderal XL or any of their ingredients, your doctor will likely not prescribe either of these drugs for you. Ask them about other medications that might be better options.

Diabetes. It’s possible that Inderal LA and Inderal XL may cause hypoglycemia (very low blood sugar). These drugs can also prevent certain symptoms of hypoglycemia, such as fast heartbeat, sweating, and shaking. This makes it difficult to know if you have hypoglycemia. Use Inderal LA or Inderal XL cautiously if you have diabetes, especially if you take insulin or other medications that lower your blood sugar. (Cautious use includes frequent blood sugar testing, consistent eating, and monitoring your symptoms.) Tell the doctor prescribing this drug for you about all your medical conditions, including diabetes.

Heart failure. Depending on which kind of heart failure you have, your doctor may not prescribe Inderal LA or Inderal XL for you. Talk with them about your best treatment options.

Liver problems. Inderal LA and Inderal XL are processed by your liver. If you have liver problems, your liver may not be able to get rid of these drugs as well as it should. This means that Inderal LA or Inderal XL can build up in your body and increase your risk of side effects. Discuss your health history with your doctor. They’ll let you know whether either of these drugs is safe for you to take.

Kidney problems. If you have kidney problems, your body may not be able to clear Inderal LA or Inderal XL as well as it should. This can cause the drug to build up in your body, which may increase your risk of side effects. Let your doctor know if you have kidney problems. They’ll determine whether either of these drugs are right for you.

Slowed heart rate. If you have certain abnormal heart rhythms, Inderal XL can cause a slowed heart rate, leading to heart block and cardiac arrest. Your doctor can determine whether it’s safe for you to take Inderal LA or Inderal XL.

Thyroid problems. Inderal LA or Inderal XL may mask certain signs and symptoms of hyperthyroidism. Your doctor can determine whether it’s safe for you to take Inderal LA or Inderal XL.

Sudden and severe drop in blood pressure. Inderal LA and Inderal XL are used to lower blood pressure and can cause a sudden drop in your blood pressure as you sit or stand up. Your doctor can determine whether it’s safe for you to take either of these drugs.

Asthma. If you have asthma or other lung problems, such as bronchitis or emphysema, your doctor may not prescribe Inderal LA or Inderal XL for you. They’ll discuss other treatment options with you that might be better.

Upcoming surgery. Tell your doctor if you are scheduled for surgery and will be given anesthetic drugs. Your doctor can determine whether it’s safe for you to take Inderal LA or Inderal XL if you plan to have surgery.

Wolff-Parkinson-White syndrome. The use of Inderal LA or Inderal XL in patients with Wolff-Parkinson-White syndrome and an increased heart rate can lead to severely slow heart rate. This condition requires treatment with a pacemaker. Your doctor can determine whether it’s safe for you to take Inderal LA or Inderal XL.

Other precautions

Be sure to talk with your doctor about your health history before you take Inderal LA or Inderal XL. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health.

Alcohol and Inderal LA and Inderal XL

Alcohol can increase or decrease the levels of Inderal LA or Inderal XL in your body. This means that consuming alcohol while taking either of these drugs can increase your risk of side effects from these medications. Or the interaction can prevent Inderal LA or Inderal XL from working as well as they should.

Talk with your doctor to learn how much alcohol, if any, is safe for you to consume while taking these medications.

Pregnancy and breastfeeding while taking Inderal LA or Inderal XL

There are currently no studies of people taking Inderal LA or Inderal XL during pregnancy. Because of this, it’s unclear whether it’s safe to take either of these drugs if you’re pregnant.

But some people who took propranolol* during pregnancy have reported problems, such as problems with fetal development (commonly known as birth defects).

Also, children whose parents took propranolol* during or just before delivery had hypoglycemia (low blood sugar level), slow heart rate, or breathing problems.

Inderal LA and Inderal XL pass into breastmilk. But it’s not known whether breastfeeding is safe while taking either of these drugs.

Talk with your doctor if you’re pregnant or planning to become pregnant or breastfeeding or considering it. They’ll help you decide the best option to treat your condition.

* Propranolol is the active ingredient in Inderal LA and Inderal XL. (An active ingredient is what makes a drug work.)

As with most drugs, you may have some side effects from Inderal LA or Inderal XL. Many of the common side effects are mild and go away after your body gets used to the medication. But some side effects can be serious and require medical attention. Talk with your doctor before starting Inderal LA or Inderal XL. They can discuss potential side effects with you and symptoms to watch for.

Here are a few examples of questions to ask your doctor:

• Does my risk of fatigue (low energy) depend on the dosage I take?
• Does avoiding sun exposure decrease my risk of developing Stevens-Johnson syndrome?
• Is cough a side effect of Inderal LA or Inderal XL?
• How do the side effects of Inderal LA and Inderal XL compare with those of other beta-blockers?

For regular updates on managing migraine or for tips on taking good care of your heart, sign up for the Healthline migraine and heart health newsletters. To share stories with others living with migraine, join the Bezzy migraine community.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.