Circadian Rhythm Alteration with Propranolol

Ever wished you could hack your sleep schedule, beat jetlag, or stay sharp through an all-nighter without feeling like a zombie? Enter propranolol—a seemingly ordinary beta blocker with some extraordinary tricks up its sleeve. From calming anxiety to resetting your internal clock, propranolol might just be the secret weapon you've been looking for to take control of your sleep and energy levels.

Overview of beta blockers

Mechanism of action

Beta blockers generally inhibit signals from the sympathetic nervous system, leading to reduced anxiety levels by limiting the heart’s ability to respond to stress.

Beta blocker subtypes

Cardioselective beta blockers mainly work on the heart by blocking beta-1 receptors, which helps lower heart rate and blood pressure. Because they focus more on the heart, they don’t affect the lungs as much, making them safer for people with breathing problems like asthma or COPD.

Non-selective beta blockers block both beta-1 and beta-2 receptors. Since beta-2 receptors are found in the lungs, blood vessels, and muscles, these drugs can affect more than just the heart. This can cause side effects like tightening of the airways, making them less safe for people with asthma or COPD.

Applications for Anxiety

This mechanism is particularly beneficial for individuals with social anxiety or general anxiety disorders, as it mitigates physical symptoms of anxiety.

Propranolol specifics

Propranolol is a non-selective beta blocker. It is the most lipophilic (fat-soluble) among them, which enables it to cross the blood-brain barrier more effectively.

Effects on circadian rhythm

When propranolol crosses into the brain, it affects the suprachiasmatic nucleus (SCN) in a way that mimics morning blue light exposure. This can lower the body’s natural production of melatonin, which might lead to insomnia and nightmares.

Application

Propranolol can be used to intentionally reduce melatonin production, making it easier to stay awake longer, such as when pulling an all-nighter. It can also be used to reset a chronically desynchronized sleep schedule or overcome jetlag.

Example: reversing a nocturnal routine

Background

Drue Wetsel, a 25-year-old software engineer, has been stuck in a nocturnal routine, habitually falling asleep at 5 am and waking up around 1 pm. He wants to reset his sleep schedule to fall asleep at midnight and wake up at 8 am to align better with a more typical workday and improve his overall health.

Circadian reset protocol

5 am: Drue goes to bed at his usual time and sets an alarm for 8 am, planning to get only 3 hours of sleep.
8 am: He wakes up, takes propranolol, and uses caffeine to power through the day on minimal sleep.
12 pm – 6 pm: Drue keeps himself busy and alert, using a brief NSDR (non-sleep deep rest) session to avoid napping and maintain energy.
12 am: Exhausted, Drue finally goes to bed at his new target bedtime, setting an alarm for 8 am to reinforce the new schedule.
Following days: Drue sticks to the midnight-to-8 am sleep schedule, using propranolol and mild stimulants as needed, until it becomes his new norm.

Additional medical applications

Thyroid storm management: Propranolol helps manage dangerously fast heart rate and high blood pressure caused by excessive thyroid hormone by slowing down the heart and easing other symptoms like anxiety and tremors.

Prevention of cardiac remodeling: propranolol can help prevent changes in heart structure caused by heart failure (however, other beta blockers are more commonly used for this purpose).

Prophylactic use in cirrhotics: variceal bleeding occurs when swollen veins in the esophagus or stomach burst and bleed due to liver disease. Non-selective beta blockers like propranolol help prevent this by reducing pressure in those veins.

Treatment of essential tremors: essential tremors cause uncontrollable shaking, often in the hands. Propranolol helps reduce this shaking, making it easier for people to do everyday tasks.

Cautions and side effects

Respiratory concerns: propranolol and other non-selective beta blockers can exacerbate asthma and chronic obstructive pulmonary disease (COPD).

Conclusion

In conclusion, propranolol is a versatile non-selective beta blocker with a range of applications, from managing anxiety and essential tremors to preventing serious complications in conditions like thyroid storm and cirrhosis. Its ability to cross the blood-brain barrier makes it particularly effective for altering circadian rhythms, offering a solution for those needing to reset their sleep schedules. However, caution is necessary, especially for individuals with respiratory conditions, as propranolol can exacerbate issues like asthma and COPD. Consult a healthcare professional for guidance before using propranolol.

Message me on X (Twitter) if you enjoyed this post or if you’ve got any corrections I should know about. Special thanks to quixoteknight for enriching this post with invaluable insights into medical pharmacology. Read what they have to say about melatonin next.