I haven’t experienced hair loss with Stelara specifically- I was losing it before I went on Stelara due to the flare itself.
It has been great for my arthritis. But not so effective for my Crohns, which was the primary thing it was meant to treat.
As it seems it is very often used for Crohns, weight gain experience for those people is likely to be really different than for someone with PsA. Crohns sufferers who go into remission will put on weight quickly, and for some of them, it may be really hard to control due to a mix of a very weird relationship with food, and a sudden change in intake requirements after many years of needing a much higher intake., and restrictions on what you can actually eat. I’m finding this hard right now.
It’s not impossible it would cause a change in weight for PsA either, but it seems much less likely to be a side effect (it wasn’t seen in the clinical studies at all). So I would not worry about it too much, except to keep tabs on it, and both raise it with your Rheumy and actively modify your diet if you note weight gain.
Joint wise I am great, I hope it works for you you too.