Because the pharmacy will refuse to sell it to you.
Source: UK based friend who says the pharmacy will refuse to sell them once they fall under BMI 25 (still overweight).
They'd prefer to be on the tiny maintenance dose but it seems to be very hard to achieve (unless you're going off the market completely).
I'll dispute that, I work for one of the online pharmacies and we won't stop selling it to you once you've reached BMI 25. We do have criteria to guard against sudden or extreme weight loss, but I think the BMI criterion for that is something like < 20 BMI (don't quote me on that, as I'm not sure, but it's not 25).
We'll also keep you on a small maintenance dose if you want, that's a conversation you'll have with your clinician and they'll judge whether it's medically appropriate. As far as I know, there's usually no reason to prevent you, though.
My friend orders from Medexpress - could you maybe share at least the first letter of your pharmacy or a hint so we can try to guess the name of the helpful one?
Oh, it's Numan. If your friend has a different experience with us than what I describe, please email me and I'll look into it (email in profile or just username at Numan.com).
As far as I know, though, you can move to us from another pharmacy even with a BMI of < 25, as maintenance has different criteria than new prescription.
I'm not a clinician, though, so I may be wrong. If you want to email me, I can ask the clinicians and tell you for sure.
Source: UK based friend who says the pharmacy will refuse to sell them once they fall under BMI 25 (still overweight). They'd prefer to be on the tiny maintenance dose but it seems to be very hard to achieve (unless you're going off the market completely).