At my school we have an On Call system.
Anyone with any sort of management responsibility (so SLT but also Heads & 2nds of Department, Heads of Year, Heads of House) has a weekly slot on the rota. If you're not in a management role but are ambitious, you can volunteer, which is quite popular as it definitely is one of the ways to earn Brownie points with senior leadership.
For any given lesson, there are at least 3 people On Call - more if it's an identified flashpoint time such as last afternoon of term or a mufti day.
If you're teaching, you email the equivalent of [email protected] if you need back up - an unruly student needs to be removed from your class OR someone wants to be excused to use the bathroom OR you need to leave the room yourself for any reason.
First On Call colleague to see it replies 'ok' - this goes to everyone else On Call, to let them know it's covered, & also the colleague who has sent up the bat signal, to let them know the cavalry are on their way.
On Call person removes disruptive student/escorts bathroom visit/minds class whilst teacher is out of room.
They then log this centrally, so if a given student is asking to be excused Every. Single. French lesson or regularly straight after break or just several random times a week, this can be investigated & dealt with - be it a quiet 'stop it, you're taking the piss' chat with the Head of Year, or a conversation with parents re medical issues.
We instituted this during covid to avoid bubbles being breached, but it actually works well & will be retained. Students who need to go know that they will be able to; lead swingers know it's not really much fun to be escorted to the loo & back with no opportunity for a little wander.
On a couple of occasions a student has said 'I'm so sorry I just can't wait for Ms Scary-Deputy to get here!' & basically bolted to the nearest loo. Fine: Ms S-D will collar them on the way back.
But yeah, it requires a fair bit of teacher input. However, after a couple of weeks once the system was imbedded, we really just don't get much in the way of unnecessary bog break requests.