Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Olanzapine is an effective and safe antipsychotic drug. Its pharmacokinetic properties are comparable to those of classical antipsychotics. Oxidative processes are mediated by the cytochrome P450 isoenzyme CYP1A2 and to a minor degree by CYP2D6. Olanzapine's main route of metabolism is by glucuronidation. Therapeutic doses result in a wide variability of serum levels; dose and serum concentration are linearly correlated. Smoking and carbamazepine induce cytochrome P450 isoenzymes and thus decrease olanzapine serum levels. Inhibition of CYP1A2 by fluvoxamine yields increased concentrations; however, clinically relevant CYP2D6 inhibition was observed only in combination with additional disposition factors, such as female gender or old age. As a rule dose adjustment is not necessary but moderate renal or hepatic impairment calls for control of serum levels to provide maximal safety during olanzapine therapy. Therapeutic drug monitoring (TDM) and toxicology studies are carried out by HPLC methods using UV or MS detection. The optimal therapeutic range of olanzapine serum levels is 20 to 40 ng/ml. Concentrations of 80 ng/ml are considered threshold for the occurrence of adverse events; however, toxicological studies showed that postmortem plasma levels are higher than antemortem levels. Lethality of high olanzapine was only observed in combination with other drugs. Moderate increases of prolactin levels were detected during administration of olanzapine. In relation to olanzapine therapy, several case reports of neutropenia and agranulocytosis appeared in the literature. Weight gain in olanzapine-treated patients does not correlate with serum levels. Olanzapine response is augmented when patients' serum levels are titrated to 20 to 40 ng/ml thereby minimizing the occurrence of side effects, thus TDM is recommended for patients treated with olanzapine.
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PMID:[Olanzapine: pharmacology, pharmacokinetics and therapeutic drug monitoring]. 1170 98

Expression of the placental hormone, prolactin-like protein E (PLP-E), a potent cytokine that acts on multiple myeloid lineages, is normally restricted to pregnancy and certain hematopoietic disease states. We hypothesized that the restricted pattern of PLP-E expression is necessary to avoid hyperstimulation of myelopoiesis. To test this idea, we have produced PLP-E transgenic mice and analyzed their steady-state blood cell levels. We find that blood cell levels remain in the normal range, and thus the constitutive expression of a cytokine of pregnancy fails to overcome the tight control of hematopoietic set points for blood cell levels. In contrast, an effect of constitutive PLP-E expression is detected during the recovery from low blood platelet levels (acute thrombocytopenia) and from low granulocyte levels (acute neutropenia) but not from anemia. Mice producing high circulating concentrations of PLP-E recover more rapidly from both thrombocytopenia and neutropenia, as seen both by an earlier increase of progenitor numbers in the bone marrow and the earlier return to normal circulating blood cell levels.
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PMID:Enhanced recovery from thrombocytopenia and neutropenia in mice constitutively expressing a placental hematopoietic cytokine. 1537 31

Body weight gain, sexual/reproductive dysfunction and hematological abnormalities are serious consequences of atypical antipsychotics treatment. No attempts however have been made preclinically to elucidate the adverse hematological impacts. Presently, effects of lactational exposure of olanzapine (4, 8 and 10 mg/kg) and risperidone (1 and 2 mg/kg) on hematology as well as lymphoid organ histopathology of mice neonates were investigated. Both olanzapine and risperidone transfers through milk and make the neonates susceptible to their adverse side effects. Corticosterone elevation tendency of both the drugs further enhance the susceptibility for immune dysfunction. Analysis of total and differential leukocytes counts revealed neutropenia with all the doses of olanzapine but only with risperidone 2mg/kg. Weight analysis and histopathology of thymus and spleen indicated a state of suppression; less in the risperidone-exposed groups. Significant plasma corticosterone elevation occurred on 4 and 8 mg/kg olanzapine exposures but not with 10 mg/kg as well as with both the risperidone doses. Elevation of plasma prolactin levels occurred dose-dependently for both the drugs. Hematological toxicity (neutropenia) might be the direct toxic effects of the drugs/unstable metabolites on circulating neutrophils and/or on the bone marrow hemopoietic cells. Direct toxicity of the drugs might also have suppressed the lymphoid organs thymus and spleen. Further, it could be associated to hormonal imbalance induced by adverse pharmacological effects of the drugs on the endocrine system. Suppression of lymphoid organs in olanzapine groups might have resulted because of corticosteronemia and hyperprolactinemia, while in risperidone it could be mediated by pronounced hyperprolactinemic effect alone.
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PMID:Effects of lactational exposure of olanzapine and risperidone on hematology and lymphoid organs histopathology: a comparative study in mice neonates. 2017 14