Propranolol

Is propranolol safe?

For most people taking it as prescribed, yes. Propranolol has been sold in the US since 1967 and is still used for high blood pressure, angina, an irregular heartbeat, migraine prevention, essential tremor and an overactive thyroid. Side effects are usually tiredness, cold hands or vivid dreams. The catches are specific: it is unsuitable for people with asthma, it must not be stopped suddenly, and an overdose is far more dangerous than for most everyday medicines. We score it 69, below metoprolol (74), mainly because of the overdose record.

US doses on the generic tablet label are wide. For blood pressure it starts at 40 mg twice a day, with a usual range of 120 mg to 240 mg a day and up to 640 mg in some people. For migraine it starts at 80 mg a day, and the extended-release capsule (Inderal LA) starts at 80 mg once a day. The NHS lists 40 mg once a day for anxiety, up to 40 mg three times a day.

Why it is used for anxiety

Propranolol blocks the effects of adrenaline on the body: the pounding heart, shaking hands and sweating that come with stage fright or a job interview. The UK licenses it for these physical symptoms; in the US this is an off-label use. In 2025 it trended on social media as a "miracle fix" for nerves, with celebrities talking openly about taking a beta-blocker before performances, and more people now get it through telehealth services (GBH News, December 2025).

The evidence for anxiety disorders, as opposed to one-off performance nerves, is thin. NICE does not recommend it for them, and a 2024 analysis in the British Journal of General Practice found poor evidence of benefit alongside significant overdose rates. Prescribing to young people in England has risen anyway: 59,717 people aged 15 to 19 received propranolol in 2023, up 44% from 2016, according to NHS data obtained by The Pharmaceutical Journal.

Overdose: the main risk

This is where propranolol differs from metoprolol and other beta-blockers. As well as slowing the heart, it blocks sodium channels and is highly fat-soluble, reaching the brain, so a large overdose can cause seizures, coma, dangerous heart rhythms and cardiac arrest. The label notes it cannot be removed by dialysis.

The data are consistent across countries:

• Australia: among 209 overdoses of 360 mg or more (2014 to 2023), 24% caused severe toxicity, 8% a seizure, 14% coma and 3% cardiac arrest. In people who took propranolol alone, half of those who took 2,000 mg or more became severely ill.
• United Kingdom: poison centres were consulted on 363 intentional overdoses in 2022 and 2023. Where the reason for the prescription was known, 111 of 121 were for anxiety, and 35 of the 159 people with a confirmed outcome died.
• Coroners: UK coroners sent several prevention-of-future-deaths reports in 2023 and 2024 after propranolol overdoses, including in a 17-year-old and a 19-year-old. The MHRA told The Pharmaceutical Journal it reviewed the drug in August 2024 and that its benefits outweigh the risks at approved doses.

The practical point: a month's supply can be a dangerous amount for someone in crisis. People who live with someone at risk of self-harm can ask the prescriber or pharmacist about smaller supplies.

Asthma, stopping suddenly and other warnings

Propranolol blocks beta-2 receptors in the lungs as well as beta-1 receptors in the heart. The US label therefore lists bronchial asthma as a contraindicationContraindicationA situation in which a medicine should not be used, because the risk clearly outweighs any benefit, such as a known allergy to it.More in the glossary, alongside cardiogenic shock, a slow heart rate and heart block beyond first degree.

Stopping abruptly can worsen angina and has been followed by heart attacks; the label advises reducing the dose over at least a few weeks, even for people taking it for migraine or anxiety, because heart disease can be silent. Older repackaged labels still show this as a boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary, while the current generic and Inderal LA labels list it first under Warnings. Propranolol can also hide the warning signs of low blood sugar, particularly in children and people with diabetes, and mask an overactive thyroid.

Several common medicines raise its levels, including fluoxetine, paroxetine, fluvoxamine and ciprofloxacin, and verapamil or diltiazem add to its heart-slowing effect. Smokers clear it faster.

How we scored it

Track record (98) and dependence (85) are strong for a drug used for nearly 60 years with no misuse potential. Serious side effects (70), regulatory warnings (70) and interactions (60) sit in the middle. Overdose marginOverdose marginHow far a normal dose is from a harmful one. A wide margin means an accidental extra dose is unlikely to cause serious harm.More in the glossary (45) is the weakest factor and pulls the score down. A lower score is not a reason to stop propranolol: talk to your doctor or pharmacist if you have concerns.