Lithium clinical side-effects

Following initial assessment, including evaluation of potential suicidality, support systems, and need for inpatient versus outpatient treatment, MW was hospitalized briefly, then followed in the community on medication along with psychotherapy. She has abstained from illicit substances and has returned to her job. She has responded well to treatment with sustained-release lithium carbonate 900 mg once daily at bedtime with a snack. Steady-state 12-hour serum lithium concentrations have stabilized at 0.9 mEq/L (0.9 mmol/L). She now returns to clinic for routine followup. She has tolerated the lithium except for a mild tremor and a gain of 7 pounds (3.2 kg). She is willing to accept these side effects for now, but asks about how long she must take medication since she is now feeling well. 

The clinical significance of this ethnic difference for psychiatry was found later. A study examining lithium tolerability found more side effects in African American patients with high RBC/plasma ratio even when the lithium levels were in the therapeutic range (Strickland etal., 1995). It is not known whether African Americans require lower doses and will respond with lower plasma levels. We do know that African Americans with mood disorders are less likely to be prescribed lithium either as primary treatment or adjunctive therapy (Valenstein etal., 2006 Kilbourne 8c Pincus, 2006). It is unknown as to whether the lack of tolerability at usual therapeutic doses is a factor. 

The clinical value of monitoring drug therapy by measuring plasma levels is probably best exemplified by reference to lithium (F6). It is a useful drug, which has a narrow therapeutic index, and treatment without reference to plasma levels is probably not ethically justified. Toxic side effects are predictable and severe. It has an acceptably long plasma half-life, and its measurement both in blood and urine is comparatively simple. Moreover, there is no problem of interference from either active or inactive metabolites. 

In this chapter we review the mechanisms of action, pharmacokinetics, side effects, and uses of lithium and the anticonvulsants as they apply to child psychiatric clinical practice. 

Long-term side effects of lithium treatment include weight gain. The treatment is associated with development of hypothyroidism in about 10-15% of cases. There is an association with kidney disease. Birch has expressed the general view that Li may interact with magnesium-dependent processes, and theoretical chemistry supports this view. Despite the widespread clinical significance of Li, there is presently no consensus on its mode of action. One postulate for the mechanism is termed hyperpolarization . Li affects the conductivity in cell transport channels. Other explanations include modulation of neurotransmitter concentrations and inhibition of Na+/K+/Mg2+/ Ca2+ ATPases. 

McConville BJ, Sorter MT, Foster K, Barken A, Browne K, Chaney R. In Lithium versus Valproate Side Effects in Adolescents with Bipolar Disorder. New Clinical Drug Evaluation Unit ProgamPresented at the NCDEU 38th Annual Meeting, 10-13 June, Boca Raton, FL 1998 144 poster no. 74. 

Since its introduction several decades ago for the occasional treatment of "psychotic excitement", lithium is still a mainstay in the treatment and prophylaxis of manic-depressive disorders [1]. The biologic basis for the clinical efficacy of lithium is not completely known. Interestingly, the agent relieves both mania and depression, states which appear to be opposites. Its therapeutic range, however, is narrow, and even at the lowest effective dosage, some unwanted side effects may occur [2]. Serum levels above 1.5 mEq/L often result in acute intoxication, which may... 

Vestergaard, R, A. Amdisen, and M. Schow. 1980. Clinically significant side effects of lithium treatment. Acta Psychiatrica Scandinavica 62 193-200. 

Group la Lithium - Lithium salts were used indiscriminately over the early part of this century for treatment of gout, epilepsy. Insomnia, hypertension and as salt substitutes in cardiac disease. Unfortunately, toxicity associated with lithium salt therapy was not known at that time. Many cases of serious side effects and deaths resulted which led to their disuse. In recent years judicious use of lithium salts, primarily lithium carbonate, for the control of manic symptoms has reestablished their utility in clinical practice. 

Vacaflor L. (1975) Lithium side effects and toxicity the clinical picture. In F. N. Johnson (Ed.) Lithium Research and Therapy, Academic PresS London pp. 211-226. 

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