LONG TERM EFFECTS OF LITHIUM CARBONATE

Abstracts: Addition of lithium carbonate to carbamazepine: hematological and thyroid effects. Less frequent lithium administration and lower urine volumeCarbamazepine is an anticonvulsant drug which is currently receiving much attention as an alternative to lithium carbonate in treating bipolar affective disorder (manic depression). Benefits have been observed when a combination of these two drugs has been used to treat patients who are otherwise resistant to treatment with either drug alone. Conflicting reports exist, however, with some indicating that the side effects of this combination treatment are highly toxic. To further investigate the effects of combination treatment on the blood and the activity of the thyroid gland, a group of 23 patients with affective disorders was examined. The patients had been previously resistant to both drugs when administered alone. All subjects were screened for the presence of seizures and other related disorders. Some patients were given gradually increasing doses of carbamazepine, while others were given a placebo. Supplementation with lithium was given to the patients at an average of 39 days after carbamazepine or placebo was begun. Blood samples were taken and analyzed throughout treatment, and several clinical changes that involved the blood and thyroid function were evident after the addition of lithium. Carbamazepine therapy alone was associated with lower total white blood cell counts, and lower neutrophils and lymphocytes. When lithium was added, the total white blood cell counts increased to levels higher than when treatment began. Antithyroidal effects where also observed during the combination treatment period, with lower thyroid hormone levels than were measured with carbamazepine treatment only. Slightly higher levels of TSH (thyroid-stimulating hormone) were noted when lithium was added to treatment. Clinical and theoretical implications of these findings are discussed.