Case Presentation:
Your 11 year old male patient with Autism level 2 without intellectual or verbal impairment and Generalized Anxiety Disorder is not tolerating sertraline well (resulting in weight gain and akathisia) with minimal positive effect. Primary concerning symptoms include: agitation, quick to anger, and difficulty with changes in routine. He previously did not tolerate trials of fluoxetine, guanfacine or aripiprazole but another physician. His mother is asking about propranolol which she read about on an autism blog she follows.
Beta-blockers:
There are medications that were developed for physical problems that have subsequently been found to be helpful for mental health problems. Several mood stabilizers, which were originally developed to be helpful for epilepsy, fall into this bucket, as do the alpha-agonists and beta blockers, which were developed for hypertension but have found to be useful for behavioral health concerns as well. This newsletter will focus on the many uses, mostly as an adjunctive treatment, of beta-blockers.
SSRIs are the first line medication treatment for anxiety disorders and are quite effective for the underlying feelings and thoughts linked to anxiety, but often aren’t as helpful for the outward behavioral and physical symptoms of anxiety. Behavioral symptoms of anxiety include: dysregulation, fight or flight response, and agitation. Physical symptoms of anxiety include: elevated heart rate, sweatiness, shaking, tremor, headache and stomachache/nausea. When these don’t respond to the combination of therapy and SSRI, it is helpful to consider alternative treatments, which can include alpha agonists and beta blockers, specifically propranolol.
Propranolol:
Propranolol is a non-selective beta-adrenergic receptor blocker that crosses the blood-brain barrier so can have effects in the central nervous system in addition to its peripheral activity, unlike most other beta-blockers. It has been around since the 1960s as an antihypertensive medication, although there are newer medications for hypertension now. When people feel anxious, their body makes more of the neurotransmitters norepinephrine and epinephrine, which historically served a survival purpose for the “fight or flight” response but can be impairing for someone with excessive anxiety. Propranolol can specifically help with the physical symptoms of anxiety including sweating and shaking but doesn’t directly treat the feeling of anxiety. It can be useful for performance anxiety and panic disorder.
There are some important guidelines to keep in mind when prescribing propranolol. Typically start with 10-20mg daily in children and 20mg in adults with a target dose of 20-40mg (40-60mg for adults) divided into two doses. There is a long acting formulation of propranolol but the minimum dose is 60mg. Someone might feel sleepy when first starting propranolol but this should resolve after a few days and is one of the reasons to start at a lower than therapeutic dose and to give the starting dose in the evening. Common side effects include: dizziness, lightheadedness, cold hands and feet and stomachache. It is important to monitor blood pressure regularly if prescribing propranolol. Use caution when prescribing with other medications that can reduce blood pressure. For example, it is not recommended to use propranolol with an alpha agonist, particularly at high doses. Its use is contraindicated in people with sinus bradycardia, heart failure, and sick sinus syndrome and should be cautioned in people with diabetes, hyperthyroidism, and asthma. It should used with caution in someone with depression because it can worsen depressive symptoms. When stopping propranolol, the medication should be tapered off to avoid discontinuation hypertension.
Studies have not found propranolol to be particularly helpful for PTSD, social anxiety and generalized anxiety. It is a medication to consider when patients have impairing physical and behavioral symptoms with their anxiety presentation. This includes panic disorder and performance anxiety. Propranolol has been studied in children with co-occurring anxiety and autism. It has been found to be helpful for behavioral dysregulation while being relatively well tolerated. It can be a tool in the medication toolbox when first line options do not work well or are not well-tolerated.
Back to the Case Presentation
You plan a trial of propranolol 10mg qday to start and increase to 10mg twice per day after one week. Parents and school report he is tolerating it well (blood pressure remains stable) and mother reports he is “not so quick to react and get upset”. The dose is titrated to 20mg twice per day with a 10mg as needed dose available. He continues with his school-based supports and autism intervention.
References:
https://www.ncbi.nlm.nih.gov/books/NBK557801/
https://pmc.ncbi.nlm.nih.gov/articles/PMC4724794/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5803020/
AUTHOR:
Charmi Patel Rao MD, DFAACAP
Co-Medical Director, Vista Hill Foundation
Health Science Clinical Professor, UCSD Department of Psychiatry
President, San Diego Academy of Child and Adolescent Psychiatry