Igor Suka/Getty ImagesA reality TV star’s claim that a beta blocker drug dulled their emotions and made them appear calm on camera has sparked a wave of social media commentary.These medicines, first developed to manage high blood pressure, are now also used to treat anxiety. But beta blockers are not “chill pills” in the way many people assume.So what are beta blockers and how can they help manage anxiety?They counter the effects of adrenalineBeta blockers are a group of medications that reduce the effects of adrenaline in the body. Adrenaline is one of the hormones released as part of the body’s natural “fight-or-flight” response, which prepares us to react to danger, stress or excitement. By blocking the effects of adrenaline, beta blockers can slow the heart rate and reduce physical symptoms such as a trembling and sweating. They are most commonly used to treat heart and circulation conditions, including high blood pressure, irregular heart rhythms, heart failure, angina (chest pain), and can also be prescribed to prevent migraines. Can they help with anxiety?Yes, but not in the way that regular anxiety medicines do.Generalised anxiety disorder is usually treated with a family of drugs called selective serotonin reuptake inhibitors (SSRIs). Other drugs include serotonin and noradrenaline reuptake inhibitors (SNRIs) and tricyclic antidepressants. These drugs help alleviate the feelings of anxiety.When we feel anxious, the body’s fight-or-flight response can kick in even where there is no physical danger, leading to the release of adrenaline. This can cause symptoms such as a racing heart, sweaty palms and tremors. For some people, these changes from the body’s stress response can feed into the anxiety, making it worse and creating a cycle that can be hard to break in the moment. Because beta blockers can help control or minimise these physical symptoms, some performers and celebrities use them to manage nerves before public appearances. Beta blockers don’t stop anxious thoughts or “switch off” emotions. Unlike regular anxiety medicines that make you feel more calm or relaxed, they only control the body’s physical response to stress, rather than the feeling of anxiety itself. This is why research suggests they may be useful to ease nerves during one-off, high-pressure events such as public speaking or performing. But they aren’t suitable for the long-term management of anxiety.Are there any side effects?No medicine is risk-free. Beta blockers have a range of side effects related to lower blood pressure. These include dizziness and lightheadedness, fatigue and weakness, and cold hands and feet.They can also disturb sleep through insomnia, vivid dreams and nightmares.It’s important that once a person starts daily beta blockers they do not abruptly stop. This is because it can cause a spike in blood pressure and induce heart palpitations.Deciding if they’re right for youIf you suffer from acute anxiety and think beta blockers may help you manage those situations, speak to your doctor. But if you have more ongoing general anxiety, then regular anxiety medications may be more suitable for you. Or, your anxiety might be treatable with a non-drug solution, such as cognitive behavioural therapy.If your doctor and you decide a beta blocker is the right treatment, you’ll be able to access one via through the Pharmaceutical Benefits Scheme with a prescription.Nial Wheate in the past has received funding from the ACT Cancer Council, Tenovus Scotland, Medical Research Scotland, Scottish Crucible, and the Scottish Universities Life Sciences Alliance. He is a Chartered Chemist and fellow of the Royal Australian Chemical Institute. Nial is the chief scientific officer of Vaihea Skincare LLC, a director of medical device company SetDose Pty Ltd and was previously a Standards Australia panel member for sunscreen agents. He is a member of the Expert Panel for the Haleon Pain Management Institute. Nial regularly consults to industry on issues to do with medicine risk assessments and medicines manufacturing, design and testing. Nial is often called as a expert witness in sports tribunals involving adverse analytical findings for elite athletes.Jasmine Lee does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.