Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ziprasidone (Geodon, Zeldox), a recently approved atypical antipsychotic agent for the treatment of schizophrenia, undergoes extensive metabolism in humans with very little (<5%) of the dose excreted as unchanged drug. Two enzyme systems have been implicated in ziprasidone metabolism: the cytosolic enzyme, aldehyde oxidase, catalyzes the predominant reductive pathway, and cytochrome P4503A4 (CYP3A4) is responsible for two alternative oxidation pathways. The involvement of two competing pathways in ziprasidone metabolism greatly reduces the potential for pharmacokinetic interactions between ziprasidone and other drugs. Because CYP3A4 only mediates one third of ziprasidone metabolism, the likelihood of interactions between ziprasidone and CYP3A4 inhibitors/ substrates is low. Furthermore, aldehyde oxidase activity does not appear to be altered when drugs or xenobiotics are coadministered. Aldehyde oxidase, a molybdenum-containing enzyme, catalyzes the oxidation of N-heterocyclic drugs such as famciclovir and zaleplon, in addition to reducing some agents such as zonisamide. Both reactions can occur simultaneously. Although in vitro inhibitors of aldehyde oxidase have been identified, there are no reported clinical interactions with aldehyde oxidase inhibitors or inducers. There is no evidence of genetic polymorphism in aldehyde oxidase, and thus it not surprising that ziprasidone exposure demonstrates unimodality in humans. Aldehyde oxidase is unrelated to the similarly named enzyme aldehyde dehydrogenase, which is predominantly responsible for the oxidation of acetaldehyde during ethanol metabolism. Consequently, it is unlikely that there would be any pharmacokinetic interaction between ethanol and ziprasidone.
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PMID:Ziprasidone metabolism, aldehyde oxidase, and clinical implications. 1523 43

Ziprasidone (Geodon) is a relatively new atypical antipsychotic medication with a unique pharmacological profile. It is indicated for the treatment of schizophrenia, but has also often been used off-label for other uses. This review summarizes its important properties, specifically the pharmacodynamic parameters, receptor-binding profile and relevance to clinical outcomes, side effects, and potential for drug-drug interactions and established clinical indications. Novel therapeutic applications and relevant clinical trials or reports are also examined. The authors review the current market and speculate on likely changes in 5 years.
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PMID:Ziprasidone: a novel psychotropic with unique properties. 1585 58

The pharmacological choices for the treatment of schizophrenia have been greatly expanded with the availability of the atypical compounds clozapine (Clozaril, Novartis), risperidone (Risperdal, Janssen-Cilag), olanzapine (Zyprexa, Eli Lilly & Co.), quetiapine (Seroquel, AstraZeneca), ziprasidone (Geodon, Pfizer Inc.) and aripiprazole (Abilify, Otsuka Pharmaceutical Co. Ltd). In this article, the effects of the newer antipsychotics and their side effects are reviewed. Key issues in acute and maintenance treatment, often lifelong, will be reviewed. Side-effect management to ensure adherence to an optimal treatment regimen will be discussed. Coexisting syndromes must be treated in concordance with the patient's clinical presentation. For treatment-resistant patients, atypical compounds are generally more effective than their typical counterparts but medication augmentation strategies are frequently recommended. Finally, the results of recent meta-analyses comparing the effects of atypical versus typical compounds will be critically reviewed and remaining gaps in the current pharmacotherapy of schizophrenia will be explored.
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PMID:Pharmacological treatment strategies for schizophrenia. 1585 89

Ziprasidone (Geodon), risperidone (Risperdal), and aripiprazole (Abilify) appear to be associated with a relatively low risk for hyperlipidemia, whereas quetiapine (Seroquel), olanzapine (Zyprexa), and clozapine (Clozaril) are associated with a relatively high risk for hyperlipidemia. Possible underlying causes of lipid dysregulation include weight gain, dietary changes, and glucose intolerance. Given the multiple cardiovascular risk factors reported for patients with schizophrenia, great care must be exercised to minimize the additional risk for hyperlipidemia when choosing antipsychotic therapy. It is recommended that a lipid panel be obtained at baseline for all patients with schizophrenia and annually thereafter for patients taking relatively low-risk agents or quarterly thereafter for patients taking relatively high-risk agents. Patients with persistent dyslipidemia should be referred for lipid-lowering therapy or switched to a less lipid-enhancing antipsychotic agent.
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PMID:Atypical antipsychotic therapy and hyperlipidemia: a review. 1586 22

Acute agitation is a common psychiatric emergency often treated with intramuscular (i.m.) medication when rapid control is necessary or the patient refuses to take an oral agent. Conventional i.m. antipsychotics are associated with side effects, particularly movement disorders, that may alarm patients and render them unreceptive to taking these medications again. Ziprasidone (Geodon) is the first second-generation, or atypical, antipsychotic to become available in an i.m. formulation. Ziprasidone IM was approved by the Food and Drug Administration in 2002 for the treatment of agitation in patients with schizophrenia. In October 2004, a roundtable panel of physicians with extensive experience in the management of acutely agitated patients met to review the first 2 years of experience with this agent. This monograph, a product of that meeting, discusses clinical experience to date with ziprasidone IM and offers recommendations on its use in various settings. In clinical trials, patients treated with ziprasidone IM demonstrated significant and rapid (within 15-30 minutes) reduction in agitation and improvement in psychotic symptoms, agitation, and hostility to an extent greater than or equal to that attained with haloperidol i.m. Tolerability of ziprasidone IM was superior to that of haloperidol IM, with a lower burden of movement disorders. Clinical trials have also shown that ziprasidone IM can be administered with benzodiazepines without adverse consequences. Transition from i.m. to oral ziprasidone has been well tolerated, with maintenance of symptom control. The most common adverse events associated with ziprasidone IM were insomnia, headache, and dizziness in fixed-dose trials and insomnia and hypertension in flexible-dose trials. No consistent pattern of escalating incidence of adverse events with escalating ziprasidone doses has been observed. Changes in QTc interval associated with ziprasidone at peak serum concentrations are modest and comparable to those seen with haloperidol IM. Results of randomized clinical trials of ziprasidone IM have been corroborated in studies in real-world treatment settings involving patients with extreme agitation or a recent history of alcohol or substance abuse. In these circumstances, clinically significant improvement was seen within 30 minutes of ziprasidone IM administration, without regard to the suspected underlying etiology of agitation. Agents with a good safety/tolerability profile, such as ziprasidone IM, may be more cost effective long term than older agents, due to reduced incidence of acute adverse effects (eg, acute dystonia) that often require extended periods of observation. Additional trials of ziprasidone IM in agitated patients in a variety of clinical setting are warranted to generate comparative risk/benefit data with conventional agents and other second-generation antipsychotics.
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PMID:Best clinical practice with ziprasidone IM: update after 2 years of experience. 1624 23

Ziprasidone (Geodon, Zeldox) is an atypical antipsychotic agent with a unique neurotransmitter receptor-binding profile. The oral formulation is indicated for the treatment of adult patients with schizophrenia and the intramuscular formulation for the control of acute agitation in these patients. In adult patients with schizophrenia or schizoaffective disorder, oral ziprasidone was effective at a dosage of 40-80 mg twice daily in patients experiencing a phase of acute illness, and at a dosage of 20-80 mg twice daily in those with chronic schizophrenia or schizoaffective disorder, including those who were symptomatically stable. Ziprasidone offers the advantage over most other atypical antipsychotic agents of being available in a fast-acting intramuscular formulation for control of acute agitation, thus providing clinicians with the option to safely and effectively transition to longer-term treatment with the oral formulation. Although careful consideration should be given to the propensity for ziprasidone to cause corrected QT (QTc) interval prolongation, albeit at a relatively low incidence, the drug generally has a favourable tolerability profile of low extrapyramidal syndrome (EPS) liability, neutral bodyweight gain, and potentially low propensity for metabolic complications. Thus, ziprasidone is an effective option for the management of patients with schizophrenia or schizoaffective disorder, with the intramuscular formulation providing a useful option for the treatment of acute agitation in these patients.
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PMID:Ziprasidone: a review of its use in schizophrenia and schizoaffective disorder. 1714 Feb 81

Ziprasidone, commercially available as Geodon capsules, is an atypical antipsychotic used in the treatment of schizophrenia and bipolar disorder. It is a BCS Class II drug that shows up to a 2-fold increase in absorption in the presence of food. Because compliance is a major issue in this patient population, we developed and characterized solubilized formulations of ziprasidone in an effort to improve absorption in the fasted state, thereby resulting in a reduced food effect. Three formulations utilizing solubilization technologies were studied: (1) an amorphous inclusion complex of ziprasidone mesylate and a cyclodextrin, (2) a nanosuspension of crystalline ziprasidone free base, and (3) jet-milled ziprasidone HCl coated crystals made by spray drying (CCSD) the drug with hypromellose acetate succinate. The formulations were characterized by in vitro methods appropriate to each particular solubilization technology. These studies confirmed that ziprasidone mesylate - cyclodextrin was an amorphous inclusion complex with enhanced dissolution rates. The ziprasidone free base crystalline nanosuspension showed a mean particle size of 274 nm and a monomodal particle size distribution. In a membrane permeation test, the CCSD showed a 1.5-fold higher initial flux compared to crystalline ziprasidone HCl. The three formulations were administered to fasted beagle dogs and their pharmacokinetics compared to Geodon capsules administered in the fed state. The amorphous complex and the nanosuspension showed increased absorption in the fasted state, indicating that solubilized formulations of ziprasidone have the potential to reduce the food effect in humans.
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PMID:In vitro and in vivo characterization of amorphous, nanocrystalline, and crystalline ziprasidone formulations. 2234 51