I know it-if you mix them together in one solution youÂ´ll get stability probs. and they wonÂ´t work perfectly anymore. Im very surprised that nearly nobody here is using topical flut. itÂ´s great stuff!I know you are affraid of syst. absorbtion. But if you use 20mg topicaly then the total sys. absorbed amount is so tiny it will not cause any probs!And its halflife is only 5h. (to compare the oral dose for cancer or switching your gender is 750mg a day) In europe many people use it and i never heard of anybody who had probs with it. You just have to limitate the amount on your scalp. For me its 1 ml of 2%Flut mixed up in spironolactone once a day.But there are people who use it twice a day and may be 3ml per aplication.So they use 120mg a day and that may cause probs for sure.