The advice regarding propranolol remains unclear, which is why it was removed from the PPH. While it useful in controlling anxiety from a racing heart, the claim that it makes the nitrite more effective hasn't yet been established.. Some argue that a racing heart more quickly uses up the limited circulating oxygen…speeding death… this has not been fully resolved.
There are certain cardiac conditions that can be accentuated by propranolol, such as significant heart failure, bradycardia (slow heart rate), or heart block. In such cases, the dose of 400 mg propranolol should be reduced..but generally 400mg will not lead to any chance of LOC (loss of consciousness).
An alternative option is to take propranolol at a lower dose for a few days prior. This approach has the advantage of minimizing any unexpected reactions to the drug, especially when combined with sn.
Propranolol can be taken as a regular dose for 48 hours prior, with doses ranging between 40 mg and 80 mg every 12 hours, to check tolerance.