Which form of applying Minoxidil is better? Injectable or topical?

Hair loss requires an in-person evaluation. I suggest seeing a hair loss expert now to evaluate and go over your condition and provide you information about your best treatment options. There are great non-invasive options like prp/progesterone which work well with Minoxidil. See an expert. Best, Dr. Emer

Comparing topical vs injected Minoxidil is difficult as it depends on other factors besides just the method of delivery. However in general topical is more convenient and more effective than injectable, so it is much more common to see used. 

Thank you for your post and question. Most commonly and safest option would be the Topical Minoxidil at 5% strength. Anything over 5% would require a prescription such as 6% or 7%. You may come across Topical liquid versus Foam Minoxidil, the liquid works better as it is better absorbed to the follicle. Hope this helps.