Northeastern University professor Raymond Booth first learned about propranolol, a drug developed to treat high blood pressure, in pharmacy school around 1978.
In graduate school, he noticed classmates using the drug not for heart conditions but to manage situational anxiety, especially during exams. Curious, he asked a friend how she knew to take it. She shrugged: everyone in her pharmacy school had used it.
“It basically decreases my heart rate and that relaxes me, because when I go in front of people, I get nervous and my heart beats faster,” Booth recalls her saying.
Those who understood the drug’s mechanism of action took full advantage of it, says Booth, an associate director of Northeastern University’s Center for Drug Discovery and professor of pharmaceutical sciences.
Today, celebrities including Robert Downey Jr. and Katy Perry have admitted to using beta-blockers to calm nerves before public appearances. Yet, according to the UK-based Pharmaceutical Journal, some experts warn that evidence supporting propranolol’s use for anxiety is limited. They also stress the need for greater awareness about the risks of misuse and overdose.
What to know about anxiety
When public speaking or even a first date makes you extremely anxious, is it worth considering this “magic pill”?
What most people call anxiety is a set of physiological reactions, thoughts and feelings triggered by uncomfortable situations, says Rachel Rodgers, an associate professor of applied psychology at Northeastern University.
Many would describe the experience as unpleasant, she says, but this state is actually similar to the excitement someone might feel before a date.
“I don’t classify feelings as being necessarily positive or negative. They’re ones that we find more or less comfortable,” Rodgers says. “What we feel in a situation is entirely based on our interpretation of what’s going on.”
Anxiety thrives on avoidance, Rodgers says.
“The more you resist experiencing those things, the more likely those manifestations will be stronger and more intense the next time the same situation occurs,” she says.
Taking medication for non-chronic anxiety, Rodgers says, can distance people from fully experiencing sensations that, over time, they might learn to manage.
“There is much less chance that one day you will adore public speaking if every time you do it, you take something that takes away the sensations,” Rodgers says.
Anxiety disorders, by contrast, cause symptoms to persist, leading to significant distress and dysfunction and often interfering with daily life.
“If you have agoraphobia to the point that you’re no longer leaving your house, this is preventing you from engaging in your daily life,” Rodgers says.
In those cases, anxiety medication is highly useful, she says.
Physicians typically prescribe drugs specifically approved for anxiety disorders, Booth says, such as selective serotonin reuptake inhibitors or benzodiazepines, rather than beta-blockers.
“I don’t think their first choice would ever be propranolol,” he says.
The challenge, Booth says, is that most anxiety drugs have sedative effects.
“That’s one of the holy grails of anti-anxiety research — to give someone a drug that will relieve their anxiety but not put them to sleep,” he says.
No new anxiety medication has reached the market in the last 20 years.
How propranolol works
Discovered in the early 1960s, propranolol is commonly prescribed to treat high blood pressure, or hypotension, by slowing the heart rate and reducing the force of blood against artery walls. High blood pressure can damage blood vessels and lead to serious conditions such as heart disease, heart attack and stroke.
“It’s quite effective for that,” Booth says. “And it’s also, I might say, very safe.”
It also treats irregular heartbeat and prevents chest pain caused by angina.
As a beta-blocker, the drug blocks the effects of hormones like adrenaline and noradrenaline on beta receptors located in various organs, including the heart, blood vessels and lungs. By slowing the heart, it relieves some physical symptoms of situational or performance anxiety, Booth says, such as palpitations and sweating.
“That alone can help mental anxiety,” he says.
Beta-blockers also block beta receptors associated with the nerves responsible for tremors.
Propranolol is also prescribed off-label for migraine prevention.
How to get propranolol
Obtaining propranolol is relatively easy, Booth says.
“I’ve dispensed a lot of propranolol prescriptions,” he says. “If you have high blood pressure, which is a huge indication not only in the U.S. but the whole world, you’re going to be on propranolol as one of the first drugs.”
It is a common, non-controlled medication most physicians feel comfortable prescribing off-label, meaning that the Food and Drug Administration has not approved it for anxiety.
“The reason why it’s not approved [for anxiety] is no one has spent the money to do the study, to show unequivocally to the FDA, which is a high bar, that it works,” Booth says. “Clinical studies are expensive. … Pharma is already selling plenty of propranolol for its approved indication, and actually it’s generic. Nobody’s making any money out of propranolol.”
What to know before taking propranolol
The anticipated effect of lowering one’s heart rate and decreasing the force of contraction, Booth says, is fatigue.
“Anything that lowers the performance of the heart is going to make people feel tired, and that’s a common side effect of propranolol,” he says.
Another frequent side effect is nightmares.
Taking propranolol daily without a hypertension diagnosis can lead to low blood pressure and blood pooling, Booth says, raising the risk of clots. These clots can cause a stroke, a pulmonary embolism or a heart attack.
Moreover, excessive slowing of the heart can cause cardiac failure, especially in older adults.
“They are perfect candidates for beta-blockers, because their vessels are not elastic anymore and don’t expand well to accommodate the blood coming out of the heart,” Booth says. “But a lot of elderly people already have weak hearts, and so if you give them a beta-blocker, you could send them into cardiac failure. Especially in the case of an overdose.”
Even young, healthy people can be at risk.
“If they took too much of it, that’s what would happen — they would have cardiac failure,” Booth says.
His advice: don’t take propranolol just because a friend or celebrity recommends it.
