Dear Dr DeanI am 64 and was diagnosed with bipolar disorder when I was 41. I am very prone to periods of severe depression and also experience hypomania, so I assume I am type II bipolar.I was taking 1200 mg of lithium carbonate between 1994 and 2012, and 800 mg between 2012 and 2014. In September 2014 I was informed my eGFR was 39 so I stopped taking lithium carbonate.  After a period of trying other drugs I have been taking quetiapine from February 2016 to the present day. I started on 400mg daily and have reduced to 150mg daily.I am very interested in taking lithium orotate rather than quetiapine, but am concerned about lithium toxicity. I am aware that the dose I would need is far less than on lithium carbonate, but would appreciate your opinion on whether 240 mg of lithium orotate (which I presume corresponds to 9.2mg of elemental lithium) would present a toxicity problem for me. Or is 240mg too much to start with?My eGFR has remained stable at 39 since March 2014.My psychiatrist has agreed that, were I to take lithium orotate, my eGFR would be monitored.I would value your opinion on this matter.Yours sincerelyBernard Greenwood.