For whatever reason in my own experience it literally took a week to notice a difference when I first started finasteride. It thickened right up with no shed whatsoever. But I was losing my hair extremely fast though. So maybe this is why finasteride worked so well in the beginning for me. But as quick as it came is as quick as it went. I don’t know how to describe it but it was pretty traumatic and only being 22 at the time made it more difficult to deal with. Finasteride kept my hair growing and thick for about 6 months and then after, back to thinning and an intense scalp itch that kept me up all night.
That's rough. When I was 22 I had a teenage hairline, a perfect norwood 1, and super thick, dense hair. Fast forward almost 2 years later when I'm almost 24, without any signs whatsoever I started thinning. My scalp itched like crazy and it was accompanied with tons of dandruff and shed hairs. I didn't really think much of it, balding didn't cross my mind since I believed it would happen way later in life. Halfway into being 24 years old my hair density tanked by about 35%. I have diffuse thinning, so I kept my juvenile hairline. My hair was still dense, and the existing hairs were really thick, but I could tell--others couldn't. I immediately hopped on rogaine. Experienced a small shed, and reversed a little of the miniaturization, but it thickened the hell out of my existing hair, which compensated for the loss of density. This was good for about 6 months, then another wave of hairloss kicked in. I have aggressive boughts of loss and stability. I have about 50% of my hair, but luckily I had really, really, like really f*****g had dense and thick hair, so it didn't look like I was experiencing hairloss to anyone else.
This is when I became absolutely obsessed with hairloss and scoured the internet for solutions. Upped my regimen to finasteride and that helped a ton, but just like you, experienced tolerance after about 6 months. The dreaded scalp itch came back. I'm a diffuse thinner, so I still had a near perfect norwood 1, but I think with diffuse thinners the hairloss is much more aggressive and less responsive to drugs. Upped my regimen by adding in dutasteride, which was like night and day. Experienced a big shed, but it regrew back, but the biggest things were the dreaded scalp itch was95% gone and intense thickening of the hair. Also, the waves of hairloss weren't as bad on dutasteride, but I still experienced noticeable loss. Although I wasn't losing as much hairs, the areas in the scalp where I was losing them were very inflammed and hurt to touch. And I definitely think that has to do with receptor up-regulation which was completely nuking the super sensitive hair follicles.
Now at 26, I still have a norwood 1 hairline, minor recession on the temples and hairline, but they are growing back from rogaine and derma rolling. I'm upping my regimen again by adding RU58841, in order to tackle the androgen receptor problem. Hopefully, I'll be able to salvage my hair by reducing existing dht and then blocking the androgens with RU. If that doesn't work, I'll probably end up increasing my 0.5 mg of dutasteride a day to 2.5 to nearly eradict scalp dht-- but I am worried about the sides.
f*** hairloss.