Department of Medicine, Lady Hardinge Medical College, New Delhi, India
Lithium is a popular drug in the field of psychiatry, used widely as a mood stabilizer in bipolar affective disorder. However, it has a narrow therapeutic index, between 0.6 and 1.5 mEq/L. Toxicity can occur at levels >1.5 mEq/L, hence thus monitoring of serum drug level is vital. Furthermore, the range of Lithium's therapeutic index can be further lower in the elderly, especially in the presence of renal disease, as the drug metabolism in this age group has considerable variation from an average adult. Following is a case report to exemplify Lithium Intoxication and of its narrow therapeutic index; and to develop further understanding on and the clinical implications of the age related changes that affect the pharmacokinetics and pharmacodynamics of the drug.
Therapeutic Index, elderly, serum level, intoxication
