@wendyw i know this is late, but I had a large kidney stone after taking this medication for anxiety as well. I took it for around a year and got a 7 mm kidney stone that had to be removed in 2017. I was 27 at the time and I’m a female. I later found that kidney stones are a “rare” side effect of this med. It’s been 3 years and I haven’t had one since I stopped taking the medication. I strongly believe it was due to the medicine. I take “rare” side effects more seriously now as many people including me would never think to connect the side effects to the drug. Therefore most of the time it isn’t noted or recorded by doctors.

Side note: Lots of migraine medication/seizure medication causes kidney stones too. My neurologist prescribed me some after I told her I had a stone before and was more prone to them and to not give me anything that could cause them. I read the info that came with the prescription When I got home and it said to “drink a lot of water because it could cause stones”. Make sure you do lots of research before you or him takes any more meds. It’s hard to trust anything these days.