岡田 剛史

AIM: Constipation is one of the most common adverse effects in schizophrenia treatment, and it can sometimes cause severe gastrointestinal disease. However, the results of association studies between constipation and psychotropic medications in patients with schizophrenia are inconsistent. Therefore, we investigated the characteristics of psychotropic and laxative prescriptions at discharge in patients with schizophrenia to clarify the association between psychotropics and constipation. METHODS: We analyzed the data of 139 patients with schizophrenia with or without laxative prescriptions at discharge from eight institutions in 2020. RESULTS: Sixty-two patients were prescribed laxatives at discharge. The prescription of benzodiazepines in the laxative use group (66.1%) was significantly higher than that in the non-laxative use group (39.0%) (p = 1.4 × 10-3), and the mean number of benzodiazepines in the laxative use group (1.2 ± 1.1/day) was significantly higher than that in the non-laxative use group (0.7 ± 0.9/day) (p = 2.6 × 10-3). Multivariate logistic regression analyses revealed that benzodiazepine prescriptions were significantly associated with laxative usage (odds ratio, 3.059; 95% confidence interval, 1.523-6.144; p = 2.0 × 10-3). CONCLUSION: Benzodiazepines may be associated with constipation in patients with schizophrenia. Therefore, clinicians should be cautious when prescribing benzodiazepines for the treatment of schizophrenia.

Caffeine, a methylxanthine alkaloid, works as a nonselective adenosine receptor antagonist. It is the most widely used psychostimulant drug worldwide. However, caffeine overdose can lead to acute intoxication, posing a clinical problem. Hyperthermia and hyperactivity are associated issues with acute caffeine intoxication; however, no definitive treatment exists. This study aimed to assess the ability of risperidone to attenuate caffeine-induced hyperthermia and hyperactivity while elucidating the unknown mechanisms of caffeine intoxication. The rats received intraperitoneal injections of saline, risperidone (0.25 mg/kg, 0.5 mg/kg), WAY-100635, ketanserin, haloperidol, sulpiride, or SCH 23390, 5 min after the administration of caffeine (25 mg/kg). Subcutaneous temperature and activity counts were measured using nano tag ® for up to 90 min. In vivo microdialysis was used to determine the effect of risperidone on caffeine-induced elevation of dopamine (DA), serotonin (5-HT), and noradrenaline (NA) concentrations in the anterior hypothalamus. Rats were injected with caffeine (25 mg/kg), followed by saline or risperidone (0.5 mg/kg) 5 min later. The levels of DA, 5-HT, and noradrenaline were measured every 15 min for up to 90 min after caffeine administration. Risperidone and 5-HT2A receptor antagonist ketanserin attenuated caffeine-induced hyperthermia and hyperactivity. Haloperidol and dopamine D1 antagonist SCH-23390 exacerbated hyperthermia without any effect on the hyperactivity. In the microdialysis study, risperidone treatment further attenuated caffeine-induced 5-HT elevation, but not DA and NA. Our results indicate that risperidone attenuates caffeine-induced hyperthermia and hyperactivity by blocking 5-HT2A receptor activity and may be potentially useful for treating caffeine intoxication.

BACKGROUND: Along with the improved prognosis of patients with congenital heart disease, the associated diverse complications are under scrutiny. Due to various medical restrictions on their upbringing, patients with congenital heart disease often have coexisting mental disorders. However, reports on patients with congenital heart disease and coexisting eating disorders are rare. Here, we report the case of a patient who developed anorexia nervosa (AN) following surgery for Ebstein's anomaly. CASE PRESENTATION: A 21-year-old female with Ebstein's anomaly who underwent Fontan surgery was transferred to our institution with suspected AN after >2 years of intermittent stays at a medical hospital for decreased appetite. Initially, she did not desire to lose weight or fear obesity, and we suspected that she was suffering from appetite loss due to a physical condition associated with Fontan circulation. However, the eating disorder pathology gradually became more apparent. CONCLUSION: Our experience suggests that patients with congenital heart disease are more likely to have a psychological background and physical problems that might contribute to eating disorders than the general population.