What Causes Headache And Rashes On Face After Using Minoxidil Topical Solution?

Hi Sir, This is Jagan and i am suffering from severe hair fall. I consulted dermatologist and she prescribed Minoxidil topical solution. i am using daily once. But, I am facing some side effects like headache and rashes on face.. Please suggest me, Can I continue with this topical solution ? or any alternate solution for this ?