Lithium prolactin

Use in combination with lithium or valproate for the acute treatment of mania or mixed states Antagonist of postsynaptic DA2 receptors atypical agents also block 5-HT2a receptors that increase the presynaptic release of DA thus lowering the risk of extrapyramidal symptoms and prolactin release... 

Prolactin secretion, at least in experimental animals, is increased following chronic lithium treatment, probably as a consequence of the enhanced sensitivity of posts)maptic 5-HT receptors and the decreased sensitivity of dopamine receptors. In patients on therapeutic doses of the drug, however, the plasma prolactin levels would not appear to be markedly altered. There is little evidence that circulating gonadotrophin concentrations are affected by therapeutic doses of lithium. 

A. Approximately 5% of patients taking lithium over the long term develop hypothyroidism, and thyroid status should be followed as routine care for these patients. Mr. Smith s symptoms are classic for hypothyroidism. Impairment in glucose metabolism, hepatic function, red blood cell production, and prolactin secretion are not typical complications of lithium therapy. 

Meltzer HY, Simonovic M, Sturgeon RD, et al Effect of antidepressants, lithium and electroconvulsive treatment on rat serum prolactin levels. Acta Psychiatr Scand Suppl 290 100-121, 1981... 

Mufson EJ, Cochran E, Benzing W, et al Galaninergic innervation of the cholinergic vertical limb of the diagonal band (Ch2) and bed nucleus of the stria terminahs in aging, Alzheimer s disease and Down s syndrome. Dementia 4 237-250, 1993 Muhlbauer HD The influence of fenfluramine stimulation on prolactin plasma levels in lithium long-term-treated manic-depressive patients and healthy subjects. Pharmacopsychiatry 17 191-193, 1984... 

Bromocriptine and the ergot analogues suppress prolactin activity and amiodarone can cause iodine-induced hypo- or hyperthyroidism. Lithium, which has a low toxicity threshold, passes freely into milk and significant plasma concentrations may occur in nursing infants. 

Serum prolactin concentrations in patients taking longterm (n = 15) or short-term (n = 15) lithium did not differ from controls (613). In another study, when compared with 17 healthy controls, 20 euthymic bipolar patients who had taken lithium for more than 6 months had significantly lower serum prolactin concentrations (9.72 ng/ ml versus 15.56 ng/ml), but prolactin concentrations in short-term lithium users (n = 15) did not differ from controls (614). Antipsychotic drugs were not involved. 

A 35-year-old woman who had taken lithium carbonate 800 mg/day for 2 years was also given risperidone 6 mg/ day for a manic relapse. She missed two menstrual periods and had galactorrhea. A head CT scan showed a pituitary microadenoma and the prolactin concentration was 125 pig/l (reference range up to 20 pg/1). Risperidone withdrawal resulted in disappearance of the prolactinoma. Her other symptoms persisted and did not change with olanzapine 2.5 mg/day however, bromocriptine 12.5 mg/day for 2 weeks relieved her symptoms and the prolactin concentration normalized. 

Sofuoglu S, Karaaslan F, Tutus A, Basturk M, Yabanoglu I, Esel E. Effects of short and long-term lithium treatment on serum prolactin levels in patients with bipolar affective disorder. Int J Neuropsychopharmacol 1999 2 S56. 

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