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Introduction
Lithium has been the first choice for years for the treatment of bipolar disorder, sold under the names Carbolith, Duralith, Eskalith, Lithane, Lithizine, and Lithobid. Effectiveness is maximized when serum concentrations are maintained at 1.0-1.2 mmol/L. Lithium has long been used to reduce suicide risks. Recent studies have shown lithium may also be effective in treatment against AIDS and cancer.
Bipolar (Manic Depressive) Disorder
Those with bipolar disorder have extreme mood swings between mania and depression. Manic episodes can begin abruptly or gradually, and are characterized by "significant insomnia, excessive talking, extreme confidence, and increased appetite." (3) As the episode progresses, "the patient exhibits racing thoughts, extreme agitation, and incoherence, frequently replaced with delusions, hallucinations, and paranoid fears." (3) During a depressive episode, the patient may experience "anxiety, loss of appetite, insomnia and feelings that the world has become 'colorless' or 'lifeless'." (4)
Bipolar disorder is a largely genetically inherited disorder. A child who has one parent with bipolar disorder has a 27% chance of being affected and the possibility jumps to 50-75% when both parents are affected. Seventy percent of cases begin after age 20.
Bipolar disorder can be further categorized into four subcategories, bipolar I disorder, bipolar II disorder, cyclothymiacs disorder, and miscellaneous other forms of bipolar disorder. BP I is characterized by major manic and major depressive episodes. BP II is similar in that there are major depressive episodes, but the manic episodes take the form of hypomania, a mild form of mania not requiring hospitalization. Cyclothymia is "considered a minor, chronic from of bipolar disorder and is thought to be part of a continuum, with bipolar disorder at the upper boundary and normal mood swings at the lower boundary." (5)
Treatment of Bipolar Disorder
Lithium's effect on mood stabilization was first discovered by John Frederick Joseph Cade, and was published September 1949 in the Medical Journal of Australia. Cade was testing the effect of uric acid on mice. Because uric acid is insoluble, Cade chose the most soluble salt of it, lithium ureate. He discovered this compound had a calming effect on mice. After extensive testing, he discovered that while lithium had little effect on depressed patients, manic patients became much calmer after lithium use. (4)
One of the main reasons that lithium is still used in treatment is its effectiveness in reducing symptoms and frequency of episodes. "the response rate is 70-80% for the initial and maintenance of mania, with a good response defined as fewer, less severe, and shorter manic or hypomanic episodes, although these episodes may continue to occur." (6) Losses in or lower levels of effectiveness are often reported. This can occur because of patients who difficult to work with (i.e. those who are undermotivated, disadvantaged, or noncompliant) or because too board of a range of patients was considered in the trial or research.
Discontinuation of lithium treatment should occur only if absolutely necessary and even then must be done gradually. All studies show that gradual reduction causes a much lower risk of relapse than abrupt discontinuation. After discontinuation, the risk of suicide jumps to the level it was before treatment began, [and] for the first six to twelve months, the risk is many times more - roughly twentyfold." (6)
Other Uses for Lithium
One of the other uses fro lithium treatment is in the treatment of suicide. This is mainly because of the close link between suicide and bipolar disorder. The suicide rate for those with bipolar disorder is approximately 20 percent. On average, lithium reduces suicide risk by at least six fold, while abrupt stoppage of treatment greatly increases suicide risk. (6)
Lithium's effect on AIDS is currently being studied by Vincent S. Gallicchio, Ph.D., director of international education at the University of Kentucky Chandler Medical Center. Combining lithium with AZT (Zidovudine) could cause fewer toxic effects and, by boosting immunity, could reduce the amount of virus in the body. The size and properties of lithium allow it to enter the cell nuclei and thus influence DNA. If lithium were found effective, says Gallicchio, "it would be ideal for use in poor countries where the disease is endemic and where governments can't afford to provide expensive antiviral treatment." (7)
Other studies currently being conducted are looking at lithium treatment of cancer because lithium increases white blood cell count, helping to stave off the effects of radiation and chemotherapy.
Conclusion
Bipolar disorder affects much of America. One percent of Americans have this disorder. On average, a person with bipolar will experience three to four episodes per year. However, bipolar disorder is a functioning disease. People with this disorder can function normally in society between episodes and, when properly medicated, even during mild episodes. More research is still needed in the application of lithium to the treatments of AIDS and cancer. Lithium is already thought of as a miracle drug, and that would make it even more miraculous.
References
1. Lewis, R. (1996). Evening Out the Ups and Downs of Manic Depressive Illness. FDA Consumer, 30 (5), 26-29.
2. Gelenberg, AJ, Hirschfeld, RMA, Jefferson, JW, Potter, WZ, Thase, ME. (1995). Managing Lithium Treatment. Patient Care, 29 (19), 71-86
3. Drug. Encyclopedia Britannica Online.
4. Kauffman, GB (1999, Dec 6). Lithium: A Case of Serendipit? Chemistry and Industry, 933.
5. Werder, SF (1995). An Update on the Diagnosis and Treatment of Mania in Bipolar Disorder. American Family Physican, 51 (5) 1126-1136.
6. Larson, R. (1998) Lithium Prevents Sucides. Insights on the News, 14 (18), 39.
7. More Uses for "Miracle Drug," Lithium , Sought in its 50th Year. (1999). Psychopharmacology Update, 10 (7), 1.
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