For as long as possible as when you stop you must go on to something else
or you rapidly lose bone,hence reason to stay on as long as possible. Have
been on it for nearly 10 yrs a d it's been a life saver for me.

As Pamela6 wrote, if you stop it or interrupt the every 6 months Prolia injection cycle without a replacement drug, there often is often a rebound effect that results in accelerated bone loss and increase risk of spinal fracture.
https://consultqd.clevelandclinic.org/rapid-bon...
Suspension of treatment was recommended by both my rheumatologist and dentist for some necessary dental work which ended up taking even longer than planned. I ended up with 8 vertebral compression fractures (without a fall) not too long after.
I have now done a year on monthly Evenity injections and am back on Prolia. Prolia has been the only med that has helped me hang onto my bone. (I have tried all the others with little success).
Wish doctors had provided better nutrition, exercise, dietary guidance earlier in my life ... when I had a chance to regain bone density. The problem is that I don't think that there are many who know are knowledgeable about that. I don't really trust PTs or physical trainers to provide good recommendations for those with osteoporosis. They know about exercise routines for seniors but few know about adaptations for those for us who have fragile bones. I swear an aggressive back massage by PT was what caused my vertebral fractures. I can't prove it, but I ended up in the ER that night.
Now I am just living with the limitations imposed by the change in posture and chronic pain imposed by the spinal compression. One day at a time. Realizing that I have to be my own advocate going forward.
Hope things go well for you. Everyone's genetics, lifestyle, co-morbidities etc are different. Unfortunately this is not a one-size-fits all situation.
Hope this doesn't sound like one giant whine. Hoping sharing my experience will help others.

Rapid Bone Loss and Multiple Vertebral Fractures After Denosumab Cessation

https://consultqd.clevelandclinic.org/rapid-bone-loss-and-multiple-vertebral-fractures-after-denosumab-cessation

I have taken Tymlos for two years with good results and little side affects.

I didn’t start prolia because 2 doctors told me said it was for life. I refused it because of the list of side effects.

I’m praying for 2 friends now that have been on Prolia and now have broken femurs! They were both in good shape, living their best lives before starting that drug. One is in her 60’s one is in her 70’s. I had 2 more friends that advised me not to start reclast because they felt so much worse after taking it. There has to be something better!

I think it’s time for drug companies to put their resources into some better research for osteoporosis drugs and create some without bad side effects! It seems that every drug offered causes some kind of problem. 😤

Never taken it, sorry