Most of clinical practice is based on tradition, without a basis in anything but habit. This seems to be the case with the common practice of giving lithium two or even three times daily. There is no basis for giving lithium more than once daily based on its half-life, which is about 24 hours. Further, multiple long-term studies show that there is more long-term kidney impairment with multiple daily dosing, as opposed to once daily. Given at night, many of lithium's short-term cognitive side effects are also minimized when the level peaks after being taken, since people will be asleep. It is well-known that once daily dosing of any drug enhances medication compliance, which is especially important in psychiatric conditions like bipolar illness, where patients often have poor insight or other reasons to avoid or stop taking medications. There is no reason to make an already complex disease more difficult to treat, especially when doing so causes more medical complications.