Clozapine-induced intestinal occlusion: a serious side effect.

Casalmaggiore Psychiatric Operative Unit n. 25 - "Oglio Po" General Hospital, Cremona Hospital Institutes, Italy.
Acta bio-medica: Atenei Parmensis 09/2007; 78(2):144-8.
Source: PubMed

ABSTRACT Aim of this article is to describe the first italian case reported in literature of a clozapine-induced intestinal occlusion with previous severe constipation in a 45-year-old male patient who had been treated with daily clozapine for 5 months because of treatment-resistant residual schizophrenia. When conservative treatment (intravenous fluids, fleet enema and rectal washout) was used and clozapine therapy was decreased, gastrointestinal symptoms rapidly improved and the patient had regular bowel motions within a week. Preventive measures (high-fiber diet, adequate fluid intake, stool softeners and exercise) was also used to ensure that clozapine therapy could be safely continued. Although constipation is a common and usually benign side effect of treatment with clozapine, this case-report highlights the consequences of undertreated and unrecognized marked constipation progressing to severe bowel obstruction (a complication which deserves more attention because it can lead to hospitalization and might be potentially fatal).

40 Reads
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Fulminant hepatic failure (FHF) refers to the rapid development of severe acute liver injury with impaired synthetic function and encephalopathy in a person who previously had a normal liver or had wellcompensated liver disease. The potential causes of FHF are numerous, but viral or toxin-induced hepatitis are the most common. Clozapineinduced hepatotoxicity has rarely been reported in the literature, occurs via an unknown mechanism and results in liver biochemical abnormalities that are usually of no clinical significance. In approximately 30% to 50% of patients treated with clozapine, there is an asymptomatic rise in serum aminotransaminase levels; however, there are no current guidelines for routine monitoring of liver function tests and liver enzymes during its use. Fatal fulminant hepatitis has only been reported in three patients receiving clozapine. A case of fatal FHF that occurred in a schizophrenic woman who began clozapine therapy shortly before her illness developed is described.
    Canadian journal of gastroenterology = Journal canadien de gastroenterologie 06/2009; 23(5):376-8. · 1.98 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cardiac autonomic dysfunction has been reported in patients suffering from schizophrenia. The aim of the present study was to evaluate gastric electrical activity in unmedicated patients suffering from acute schizophrenia in relation to their symptoms. Electrogastrography was performed before and after test meal ingestion in 26 patients suffering from schizophrenia and 26 matched controls. The non-linear measure approximate entropy (ApEn) was calculated for the first time from the obtained signal in addition to standardized measures. Results were correlated with the scales for the assessment of positive symptoms and negative symptoms. In addition, autonomic and abdominal symptoms were assessed by the autonomic symptom score. We found a significantly increased amount of tachygastria and arrhythmia within the signal of the activity of the gastric pacemaker before and after test meal digestion in patients compared to controls, indicating increased sympathetic modulation within the enteric nervous system. A significant difference was observed for slow wave, which represents the dominant frequency of gastric pacemaker activity, indicating gastric dysmotility in our patients. The elevated ApEn measure points to increased complexity and dysregulation. In addition, we have observed a correlation between delusions and tachygastria. Sympathetic function seems to be altered in the enteric nervous system of patients suffering from schizophrenia. Future studies need to explore the influence of the disease on different branches of the autonomic nervous system and clinical consequences of enteric dysfunction. Our findings point to a possible systemic autonomic imbalance that needs to be studied in respect to the neurobiology of schizophrenia.
    Progress in Neuro-Psychopharmacology and Biological Psychiatry 08/2009; 33(7):1236-40. DOI:10.1016/j.pnpbp.2009.07.007 · 3.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Therapeutic drug monitoring of plasma clozapine and of its principal plasma metabolite N-desmethylclozapine (norclozapine) (predose or "trough" sample) can help in monitoring adherence, in dose adjustment, and in minimizing the risk of toxicity. To obtain data to assist in the interpretation of analytical results, the results from a clozapine therapeutic drug monitoring service, 1993-2007, have been audited. There were 104,127 samples from 26,796 patients [18,750 (70%) men aged at time of first sample (median, range) 34 (10-89) years, and 7763 (30%) female aged 38 (12-90) years]. Clozapine was not detected (plasma concentration <0.01 mg/L) in 1.5% of samples (prescribed clozapine dose up to 900 mg/d). Plasma clozapine was either below 0.35 mg/L or greater than 0.60 mg/L in 42.5% and 28.4% of samples, respectively; in 0.4% samples plasma clozapine was 2.0 mg/L or more. Although plasma clozapine was broadly related to prescribed dose, there was much variation: 1.2% of samples had plasma clozapine >1.0 mg/L at prescribed clozapine doses up to 150 mg/d (76.2% < 0.35 mg/L), whereas 23.3% of samples had plasma clozapine < 0.35 mg/L at doses of 850 mg/d and over (18.0% > 1.0 mg/L). The highest plasma clozapine and norclozapine concentrations encountered were 4.95 and 2.45 mg/L, respectively. Although the median plasma clozapine:norclozapine ratio was 1.25 at plasma clozapine concentrations < 0.35 mg/L, the median ratio was 2.08 at plasma clozapine concentrations > 1.0 mg/L. Data (median, 10th-90th percentile) for both clozapine and norclozapine by prescribed clozapine dose band are useful in assessing partial adherence. Analysis of the plasma clozapine:norclozapine ratio by clozapine concentration provides clear evidence that clozapine N-demethylation becomes saturated at higher plasma clozapine concentrations and adds urgency to the requirement for dose adjustment should smoking habit change. A clozapine:norclozapine ratio greater then 2 suggests either a nontrough sample, or that clozapine N-demethylation has become saturated.
    Therapeutic drug monitoring 05/2010; 32(4):438-47. DOI:10.1097/FTD.0b013e3181dad1fb · 2.38 Impact Factor
Show more


40 Reads
Available from