Inderal (propranolol) belongs to a group of drugs called beta-blockers that block Beta-adrenergic receptors present in the heart, liver, pancreas, blood vessels, and the bronchial tree. This blockade of receptors can bring about changes in their function. The use of Inderal has been advised in conditions related to the heart and is limited for individuals experiencing asthma and diabetes.
Although not classified as an anxiolytic (antianxiety and antipanic), this drug is sometimes used “off label” as an anxiolytic to treat anxiety and panic. It is also prescribed, in some cases, to treat tremors and anxiety related to Parkinsonism, migraines, and various heart conditions such as arrhythmia and angina.
How Does Inderal Work?
This medication acts on Beta-1 and Beta-2 receptors in the heart and the bronchial tree. Apart from this, Inderal’s inhibitory activity on the norepinephrine transporter (causing an increase in the release of norepinephrine in synapses) causes stimulation of Alpha-1 adrenoreceptors. This results in a decreased heart rate, which contributes to its anxiolytic effects.
- What is a safe dose of this drug?
- Palpitations and anxiety: An initial dose 40 mg once daily can be used to relieve anxiety, sweating, and palpitations. Dosage may be increased to 40 mg, three times daily.
- Hypertension: Initially, a dose of 80 mg twice daily should be used and it can be increased in weekly intervals to 160 mg to 320 mg.
- Migraine: Inderal may be used to treat migraines in a loading dose of 40 mg two to three times daily and maintenance doses of 80 mg to 160 mg.
- How does my body process this drug?
This medication, when given orally, has its onset in one two hours after administration. When given in a sustained release capsule, the onset time increases to about four hours after administration. The duration of action of this medication is 6 to 12 hours. For the sustained release capsule, it is 24 to 34 hours, after which it is metabolized completely by the liver. Liver disease can decrease metabolism and increase the effects of this drug.
- Is it safe to use this drug while pregnant?
The U.S. Food and Drug Administration (FDA) classifies this drug in pregnancy category C, which indicates it should only be used during pregnancy if there are no alternatives and the benefits outweigh the risks. In pregnancy category C, drugs have shown adverse effects on the fetus in animal studies, but there are no well-controlled studies available for humans.
Find a Therapist
This medication has off-label use for treating anxiety and panic, both of which are conditions regularly addressed with various types of psychotherapy. If you are prescribed this drug for anxiety or panic, please consider finding a therapist or counselor to complement your drug treatment. A therapist may help you understand what you are experiencing better, teach you healthy coping strategies, and help you develop a good self-care routine to mitigate symptoms in the future.
Adverse Drug Interactions
This medication can negatively interact with the following:
- Antihypertensive drugs (blood pressure drugs): This medication can cause hypotension and can lead to fatigue and lethargy if combined with blood pressure medication.
- Diltiazem, Verapamil, Cimetidine, and Hydralazine: These drugs cause a decrease in the breakdown of Inderal, leading to an increase in its concentration.
- Pain medications: Pain medications may cause a decrease in the antihypertensive effect of this drug.
- Other interactions: Care must be taken if the patient is suffering from a long-term kidney or liver disease, asthma, bronchitis, emphysema, heart failure, or diabetes.
Possible Side Effects
The adverse effects of this medication are common among beta-blockers. The hypotensive (blood pressure) effects are the most common. It can also cause lethargy and fatigue. Due to the decrease in heart rate, the blood flow to the extremities is decreased, sometimes causing cold hands and feet. Some rare adverse effects include vivid dreams, dry eyes, and visual disturbances.
In case of serious side effects from this medication, a doctor should be consulted immediately. Serious side effects may include the following:
- Irregular heartbeat
- Chest pain
- Swollen hands or feet
- Weight gain
Less serious side effects may include the following:
- Drowsiness, tiredness, or weakness
- Vomiting, nausea, constipation, or diarrhea
- Sleep difficulties
- Difficult or frequent urination and rash
- Dizziness or lightheadedness
You should not stop taking Inderal abruptly; you must taper off of this medication slowly over time. Abruptly stopping this medication can cause chest pains, heart beat irregularities, and heart attack. You can reduce the symptoms you feel during withdrawal by developing a safe plan to discontinue this drug with your health care provider.
- Half Inderal LA 80mg capsules. (2012, March 26). Retrieved from http://www.medicines.org.uk/guides/inderal/anxiety
- Inderal. (n.d.). Retrieved from http://www.drugs.com/cdi/inderal.html
- Monson, K. (2013, July 1). Inderal overdose. Retrieved from http://blood-pressure.emedtv.com/inderal/inderal-overdose.html
Page content reviewed by James Pendleton, ND.