I had an illness a few years ago that lingered the better part of two years until I was feeling almost 100%. The stress to my body thinned my hair & had it falling out pretty severely. Before that, at 46 I had a FULL head of hair with zero thinning.
I'm not someone who could pull off being bald, so I tried every holistic, natural remedy I could find, but none of them did squat. At my wits end, I decided to try Finasteride. I went on Hims & sent a pic of my hair line, which honestly didn't show anything, but they approved me for the pills. Which means I think they just rubber stamp anyone who wants them.
Took them for the better part of two years & it restored the overall thickness and health of my hair along with most of the patches of my scalp that were almost bare. I stopped taking it about 4 years ago & my hair mostly looks like it did before I got sick 7-8 years ago.
I will say, I was very lucky to have a lot of hair before I became ill & I did something about it before it was past the point of no return. If you are bald or have bad thinning spots, I don't think there's any hope short of a transplant.
However if you're just starting to thin, it's worth a shot...the pills worked really well for me. Some guys have to take them forever, but I was lucky I just needed a jump start to my follicles which were dormant after that long illness & could stop taking them when I felt the thinning had ceased.