Beta blockers are routinely prescribed to ME/CFS patients who have orthostatic intolerance. But because of the medication’s effects on heart rate, it can be challenging to incorporate heart rate monitoring into the picture. After some uncertainty, I have managed to do it and would like to share what I learned.
I’ve blogged extensively about using a heart rate monitor to help me pace my activities. For many months, I kept the monitor set at 95 beats per minute, my anaerobic threshold on the second day of my exercise test. By wearing the monitor constantly, I captured multiple episodes of elevated heart rate accompanied by dizziness, nausea and sweating. And I was frustrated that my alarm would sound when I climbed a single flight of stairs or took a shower.
I received conflicting advice from two ME/CFS experts. One advised reducing my activity level further in order to avoid setting off the alarm. The other suggested taking beta blockers to steady and lower my heart rate. The first expert’s concern with beta blockers is that it would lower my heart rate, but not affect my anaerobic threshold. That expert was worried that if my heart rate monitor did not go off as frequently, I would naturally increase my activity level and risk overdoing it.
After thinking about it, and listening to other patients’ experiences, I decided to give beta blockers a try. I kept my heart rate monitor set for 95 beats per minute, and knew I would have to be very cognizant of my perceived level of exertion in order to avoid overdoing it. Several months later, I give two thumbs up to beta blockers!
The first thing I noticed on the beta blocker was that my heart rate dropped, as expected. Before the medication, I would exceed 95 beats per minute every time I climbed a flight of stairs. On the medication, I rarely exceed 90 bpm. After showering, my heart rate dropped from 98 bpm to 80 bpm. On average, I think my heart rate is about 10 beats per minute lower on the medication.
Those awful tachycardia episodes of elevated heart rate, nausea, etc have virtually disappeared. And it is so much easier to get up in the morning. Every day it was a struggle for me to get up, think clearly, and start moving around. I frequently felt a little nauseous, and I always felt like I was carrying 50 pounds on my shoulders just to get up and to the bathroom. With the beta blockers, that has become much easier. I don’t feel good in the morning, but I can get up without nausea and can start thinking about the day ahead. It is not the huge act of will and stubbornness that it used to be to just get out of bed.
Am I overdoing it? Am I crashing more as a result of masking the measure of my anaerobic threshold? That is more difficult to say. I am still crashing, and still ending the day (crash or not) in a puddle of pain and exhaustion. But there have been some unusual circumstances. Illnesses in my family have taken a severe physical and emotional toll on me. At the same time, I’ve been unusually active in this blog, advocacy efforts and FDA-related activities. So of course I am crashing, and that’s never pretty. I really can’t say for certain if the beta blockers have helped extend my capacity (like they did for Sue Jackson) or made me made me more vulnerable to overdoing it. But the worst-case scenario that Expert One worried about – that artificially lowering my heart rate would lead to more crashes – also does not seem to have occurred.
Beta blockers, like all medications, are not side effect free. I was concerned about some symptoms I have been experiencing and whether they might be a result of the beta blockers. Under my doctor’s advice, I stopped the beta blockers for a week. My heart rate shot back up within a day, and the “side effect” did not dissipate. I was happy to restart the medication after that week-long experiment.
For me, beta blockers have helped with the tachycardia and orthostatic intolerance symptoms. I’m not sure it has extended my limitations, but it hasn’t really hurt either. As with everything in ME/CFS, your individual experience may differ from mine. But it is possible to use a heart rate monitor while on beta blockers. Just remember that your anaerobic threshold hasn’t changed, so you will have to rely on your perceived exertion as well as the monitor alarm to pace your activities.