When I was on lithium, my pharmacy had been dispensing 300mg capsules so I would take 2 a day. Every time I got the lithium it would look different as it was from different suppliers. Then one time they dispensed in 600 mg capsules and I wasn't doing well so I didn't think to read the label. I ended up toxic and in the hospital for 5 days on an IV. Now I read the label every time I have my meds filled.