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 a new antipsychotic drug, pharmacodynamically similar to clozapine, but putatively devoid of haematological iatrogenicity. We report a case of relapse of previously clozapine-induced neutropenia after olanzapine treatment.
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PMID:Olanzapine-induced neutropenia after clozapine-induced neutropenia. 1047 Jul 6

Olanzapine is a tricyclic neuroleptic agent that due to structural similarities was expected to be a safe alternative to clozapine, which has a 0.5-2% risk of agranulocytosis. So far, only rare cases of leukocytopenia and thrombocytopenia have become known. In the association, "Drug Safety in Psychiatry", which is made up of 25 German psychiatric hospitals, two cases of olanzapine-induced neutropenia occurred in patients with chronic schizophrenia. The adverse drug reaction was noticed 17 days after the first intake of olanzapine in case 1 and more than 5 months after the first intake in case 2. In the second case, a reexposure to olanzapine caused the neutrophil cells to decrease again. There were no clinical signs of an infection, and the blood cell counts increased immediately to normal ranges after discontinuation of olanzapine. No special treatment was necessary.
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PMID:Two cases of olanzapine-induced reversible neutropenia. 1050 86

We report a 2-year experience with olanzapine treatment (20 mg daily) in a 65-year-old male patient with treatment-resistant paranoid schizophrenia, who had previously developed leucopenia and neutropenia first on clozapine and, subsequently, also on risperidone. Olanzapine seems to be safe in this patient, since no major decreases of haematological parameters were observed. The only exception was a brief decrease of leucocyte and neutrophil (but not erythrocyte or platelet) counts during influenza-like viral infection. However, the control of psychotic symptoms on olanzapine is not as good as on clozapine.
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PMID:Olanzapine appears haematologically safe in patients who developed blood dyscrasia on clozapine and risperidone. 1095 65

Olanzapine is an atypical antipsychotic medication frequently used in the management of psychotic states. While it has proved to be safe compared to clozapine with regard to haematotoxicity, because it has only been available for a few years, full documentation of its haematological side-effects remains incomplete. We report a case of olanzapine-induced leukopenia with associated neutropenia. Since clozapine-induced haematotoxicity has been associated with characteristic human leukocyte antigen (HLA) groups, HLA typing was determined in this patient. Following failure with typical antipsychotic medication, the patient received 10 mg/day of olanzapine. Three weeks later, he developed fever and a significant decrease in leukocyte count. Olanzapine was immediately discontinued. HLA typing was determined. The white cell count returned to normal and the fever, most probably secondary to the low white cell count, subsided with antibiotic treatment. HLA typing results were: A1 24, B7, B35, DRB1*15, DRB1*11, DRB3*01-03, DRB5*01-02. Olanzapine may induce serious leukopenia and neutropenia. HLA typing in this single patient demonstrated a distinct haplotype compared to that previously observed in clozapine-induced haematoxicity.
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PMID:Olanzapine-induced leukopenia with human leukocyte antigen profiling. 1119 61

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

Olanzapine is an atypical antipsychotic with a low incidence of extrapyramidal-motoric side effects. Its chemical structure is related to clozapine, which is known to induce neutropenia in up to 3% and agranulocytosis in approximately 1% of patients. It has been discussed controversially whether olanzapine also has a potential to induce neutropenia and agranulocytosis. Up to now, seven case reports of haematopoetic disturbances during olanzapine treatment have been published, including one case of olanzapine-induced agranulocytosis (Naumann et al. 1999), two cases of neutropenia (Steinwachs et al. 1999) and one leucopenia (Meissner et al. 1999). We report three subjects with reversible neutropenia under olanzapine, with rapid normalisation of neutrophil cell counts after discontinuation of olanzapine. In one case neutropenia occurred after administration of a single dose of olanzapine, in another case after 6 weeks of treatment. In both cases, patients had no clinical complications. In the third case, neutropenia appeared after 1.5 years of treatment followed by development of pneumonia. Two cases were recorded within the German drug surveillance project (AMSP); the third case was observed in a randomised, double-blind, multicentre study comparing olanzapine with clozapine.
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PMID:Reversible neutropenia during treatment with olanzapine: three case reports. 1554 18

Clozapine is a well-known antipsychotic to cause fatal agranulocytosis but there are only a few case reports about the risk of leukopenia and agranulocytosis associated with other atypical antipsychotics. Olanzapine has structural pharmacological similarities to those of clozapine and reports about haematological adverse effects of olanzapine include three groups: the first group includes cases of olanzapine-induced neutropenia, the second informing that olanzapine is safe after clozapine induced agranulocytosis and the third group forms prolongation of clozapine-induced leukopenia with olanzapine use. The aim of this paper is to report a case of prolongation of clozapine-induced leukopenia despite olanzapine treatment and discuss leukopenia caused by atypical antipsychotic use in the light of recent and limited literature.
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PMID:Prolongation of clozapine-induced leukopenia with olanzapine treatment. 1663 Dec 95

Neutropenia and agranulocytosis are risks known to occur with phenothiazines and clozapine. The mechanisms responsible for these conditions currently remain unclear. To our knowledge, no case of fatal agranulocytosis as a result of olanzapine treatment was reported in the literature. Thus any case of severe neutropenia occurring in a patient receiving olanzapine is alarming to clinicians. First, a review of the literature produced 41 anecdotic cases of neutropenia or agranulocytosis during treatment with olanzapine (Zyprexa) reported in a total of 24 publications. Second, we report a case of neutropenia, which proved to be fatal in a schizophrenia patient receiving olanzapine and thiazide. The cause of the death was Myelodysplastic syndrome. There is not enough evidence to prove the involvement of either olanzapine or hydrochlorothiazide or the interaction between them in this patient's myelodysplasia. Bone marrow cytogenetic study confirmed the deletion of the long arm of chromosome 11, as reported in myeloid leukemia. If this patient would have died suddenly without the laboratory investigations that lead to the diagnosis of myeloblastic leukemia, the cause would have been probably and wrongfully allotted to treatment with olanzapine.
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PMID:Fatal agranulocytosis: the use of olanzapine in a patient with schizophrenia and myelodysplasia. 1697 52

Olanzapine-induced neutropenia is a rare adverse effect that is currently poorly described in literature. Although neutropenia is a known adverse effect of clozapine, it has been associated with the use of other antipsychotic medications like olanzapine. This case report describes and reviews a case of olanzapine-induced neutropenia in a schizophrenic patient. Although the mechanism of antipsychotic-induced neutropenia is still debated, this report attempts to discuss current theories as well as supply evidence in literature of this rare but potentially dangerous adverse effect.
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PMID:Olanzapine-Induced Neutropenia. 2626 27