Try the link below which shows a comparison of Minoxidil and Carvedilol. I have no experience with Minoxidil but I do have experience with Carvedilol which is a similar drug. The paragraph below this link explains my Carvedilol experience which caused me to write this reply.
http://www.comparical.com/comparison/carvedilol-vs-minoxidil-NzI0Nzk
I took one 3.125 mg pill of carvedilol (first prescription) and then after 3 or 4 hours took a shot from an albuterol inhaler. I spent the next 3 hours sitting down trying to breathe. I did not take another pill. I had been having breathing problems before this time, hence the albuterol inhaler, but nothing remotely like this 3 hours. I don't know if this really severe breathing problem was due specifically to the carvedilol or the combination of the carvedilol and albuterol. However, when I looked at the counter indications it should never have been prescribed since I had asthma or bronchitis.