Positives

• One person with ME/CFS found that propranolol significantly increased their exertion capacity, suggesting it was beneficial for managing postural tachycardia symptoms Reddit.
  
  

Negatives

• One patient experienced a severe episode of post-exertional malaise after switching back to propranolol from another beta blocker, indicating it might not be suitable for everyone Reddit.
  
  
• A patient reported that propranolol worsened their intolerance symptoms, despite its effectiveness for postural tachycardia, highlighting variable responses to the medication Reddit.
  
  

Hurdles & Side Effects

• A patient noted that propranolol prevented their heart rate from increasing sufficiently during exercise, which could limit physical activity for some users Reddit.