https://www.theguardian.com/society/2016/aug/14/lithium-should-be-more-widely-used-for-bipolar-disorder-researchers-say
Please read the article above and the see commentary below:
I do think that lithium is underutilized for bipolar disorder. Compared to depakote or other second generation antipsychotics it has a lower incidence of long-term metabolic side effects and as good or better efficacy. I think the tricky part about lithium is education regarding keeping hydration status, salt intake, and NSAID avoidance in a population of patients that may be inherently mentally unstable. Therefore, it really only seems ideal if the patient is younger (good renal function), without comorbidities that may impact hydration or salt balance (alcohol use disorder, CHF), and functioning well enough to recognize signs & symptoms of toxicity early. This is probably why only around 10% end up on lithium as it's hard to find bipolar patients that are good candidates and the neurologic toxicity when things go wrong is quite severe.
As far the emotional numbing component this is not really unique to lithium as valproic acid and second generation antipsychotics also frequently lead to feeling this way.
Posted by Ben Malcolm, PharmD, Assistant Professor of Pharmacy Practice, WesternU College of Pharmacy