Just to follow up on this. Based on actual research a .2% nitro is not going to have a big impact, A study done in 1994 showed that a 10% Nitro ointment was less effective than Minoxidil (2%) . Std hair Minoxidil is 5%. While all of the concerns above are worth considering at .2% the risks are low. I have handled Nitro since 1995 in various configuration. However why bother if over the counter Minoxidil works better.