USA hormone replacement therapy (HRT) industry?

I recently stumbled across an HRT business, which I don't even know if I can legally own if I'm not a doctor. Based on my limited understanding of the industry from my own research as someone interested in the science of fitness, it seems like it could be pretty lucrative: it's mostly an out-of-pocket expense since health insurance doesn't cover it and people can be on it indefinitely --> recurring + sticky revenue.

My main concern is legal/regulatory risk. While I personally believe that anyone who wants to should be able to, for example, increase their testosterone or take exogenous human growth hormone under the supervision of a doctor, I would imagine that it looks to the outside world like HRT customers are really just steroid users who happen to pay a premium to get it legally. In addition, I see marketing for some HRT clinics that advertise injectable supplements or proprietary blends of supplements (e.g. injectable vitamin B). All seems like a prime target for regulators.

If anyone has any thoughts on the HRT business or even similar types of businesses (out-of-pocket medical for less-than-accepted medical work, and perhaps excluding traditional plastic surgery), I'd love to hear them!