I watched my husband go into kidney failure and be put on dialysis due to lithium toxicity (he was being monitored correctly but went toxic anyway). To add to the trauma of that situation, the dialysis pulled all of his meds off his system at once and put him into psychosis. He was in ICU for a week, and it was an awful experience.

Having watched that happen, neither of us will go near the stuff ever again. We came within hours of permanent kidney damage and/or death. Yes, it is rare to have that severe a reaction, but when you've witnessed it first hand, it has a way of making you a believer in the danger of that medication.