Treatment Strategies for Clozapine-Induced Sialorrhea: A Systematic Review and Meta-analysis.

BACKGROUND: Clozapine is the most effective medication for treatment-refractory schizophrenia. However, it has a high burden of adverse events, including common adverse events such as sialorrhea. Sialorrhea can lead to severe physical complications such as aspiration pneumonia, as well as psychological complications including embarrassment and low self-esteem. Compromised adherence and treatment discontinuation can occur due to intolerability. There have been no meta-analyses examining strategies to mitigate clozapine-induced sialorrhea. METHODS: We systematically searched Chinese and Western research databases for randomised controlled trials examining agents for clozapine-induced sialorrhea. No limit to language or date were applied to the search. Where sufficient data for individual agents was available, pairwise meta-analyses were conducted. Results were provided as risk ratios and number needed to treat. Sensitivity analysis was conducted by study quality. Adverse events were provided as number needed to harm. RESULTS: 19 studies provided data for use in the meta-analysis. Improvement in clozapine-induced sialorrhea was seen in meta-analyses of propantheline (studies = 6, risk ratio [RR] 2.38, 95% confidence interval [CI] 1.52-3.73; number needed to treat [NNT] 3, 95% CI 1.9-2.7), diphenhydramine (studies = 5, RR 3.09, 95% CI 2.36-4.03; NNT 2, 95% CI 1.5-2.0), chlorpheniramine (studies = 2, RR 2.37, 95% CI 1.59-3.55; NNT 3, 95% CI 1.6-3.5), and benzamide derivatives (odds ratio [OR] 6.93, 95% CI 3.03-15.86). When meta-analyses were limited to high-quality studies, all these results remained significant. Single studies of benzhexol, cyproheptadine, doxepin and Kongyan Tang showed promise. Propantheline increased rates of constipation with a number needed to harm (NNH) of 9 (95% CI 4.2-204.1). CONCLUSION: Clozapine-induced sialorrhea is a potentially serious adverse event. Included studies in this meta-analysis were limited by poor study quality. Diphenhydramine, chlorpheniramine and benzamide derivatives appear to have the best supporting evidence and lowest reported adverse events. Caution should be exercised when using propantheline given its increased risk of constipation.

A subchronic toxicity study of Radix Dipsaci water extract by oral administration in F344 rats.

Radix Dipsaci, the dried root of Dipsacus asperoides C.Y. Cheng & T.M.Ai, has therapeutic effects on various disorders, and in particular, bone and joint disease. Despite such ethnomedicinal benefits, there is very little information regarding its in vivo toxicity or adverse effects. This study was conducted to evaluate the potential toxicity of the Radix Dipsaci water Extract (RD-wE) by using F344 rats. The RD-wE was administered orally to rats at doses of 0, 125, 250, 500, 1000, and 2000 mg/kg body weight (bw)/day for 13 weeks. During the treatment period there were no mortalities attributed to RD-wE. Moreover, no toxic effects were observed with regard to body weight, clinical pathology (hematology, clinical biochemistry, and urinalysis), and anatomic pathology (gross findings, organ weight, and microscopic examination). The changes related to the treatment were excessive salivation at the mouth and soft feces, observed in male and female rats at 1000 or 2000 mg/kg bw/day, but these were not accompanied by any microscopic correlate or other pathophysiological changes. Based on these results, the oral no-observed-adverse-effect level of the RD-wE was considered to be 2000 mg/kg bw/day in both genders, although the target organs were not determined under the current experimental conditions.

Application of data mining and visualization techniques for the prediction of drug-induced nausea in man.

The therapeutic value of many drugs can be limited by gastrointestinal (GI) adverse effects such as nausea and vomiting. Nausea is a subjective human sensation, hence little is known about preclinical biomarkers that may accurately and effectively predict its presence in man. The aim of this analysis was to use informatics and data-mining tools to identify plausible preclinical GI effects that may be associated with nausea and that could be of potential use in its prediction. A total of 86 marketed drugs were used in this analysis, and the main outcome was a confirmation that nausogenic and non-nausogenic drugs can be clearly separated based on their preclinical GI observations. Specifically, combinations of common preclinical GI effects (vomiting, diarrhea, and salivary hypersecretion) proved to be strong predictors. The model was subsequently validated with a subset of 20 blinded proprietary small molecules and successfully predicted clinical outcome in 90% of cases. This investigation demonstrated the feasibility of data-mining approaches to facilitate discovery of novel, plausible associations that can be used to understand drug-induced adverse effects.

Treatment effects of traditional Chinese medicines Suoquan Pill and Wuling Powder on clozapine-induced hypersalivation in patients with schizophrenia: study protocol of a randomized, placebo-controlled trial.

BACKGROUND: It is reported that 30% to 80% schizophrenia patients suffered from hypersalivation when taking clozapine. Some investigations of the use of formulas of traditional Chinese medicine (TCM) to treat clozapine-induced hypersalivation suggested their potential treatment effects. In these formulas, Suoquan Pill (SQP) and Wuling Powder (WLP) were suggested to have therapeutic effects in improving clozapine-induced hypersalivation. METHODS AND DESIGN: A prospective, double-blind, randomized, placebo-controlled study will be conducted to test the therapeutic effects of SQP and WLP in relieving hypersalivation in patients taking clozapine. A total of 45 patients will be enrolled into this study with 15 in each treatment group. Patients will receive medication according to their assigned group. Either SQP 10 g per oral dose twice daily, WLP 10 g per oral dose twice daily or placebo powder 10 g per oral dose twice daily will be prescribed to the patients for 8 weeks. The Drooling Severity Scale, Nocturnal Hypersalivation Rating Scale and sialoscintigraphy will be used as the primary outcome measures; the Clinical Global Impressions Severity, the Positive and Negative Syndrome Scale, the Abnormal Involuntary Movement Scale, the Simpson-Angus Scale and the TCM constitutional scale will be used as the secondary outcome measures DISCUSSION: It is hypothesized that SQP and WLP will have a beneficial effect in controlling clozapine-induced hypersalivation symptoms. It may also improve the life quality of psychotic patients by improving their mental status. TRIAL REGISTRATION: ClinicalTrials.gov (Identifier: NCT01045720).

Pharmacological interventions for clozapine-induced hypersalivation.

BACKGROUND: Clozapine is widely used for people with schizophrenia. Although agranulocytosis, weight gain, and cardiac problems are serious problems associated with its use, hypersalivation, sometimes of a gross and socially unacceptable quantity, is also common (30-80%). OBJECTIVES: To determine the clinical effects of pharmacological interventions for clozapine-induced hypersalivation. SEARCH STRATEGY: We searched the Cochrane Schizophrenia Group Trials Register (March 2007), inspected references of all identified studies for further trials, contacted relevant pharmaceutical companies, drug approval agencies and authors of trials. SELECTION CRITERIA: We included randomised controlled trials comparing pharmacological interventions, at any dose and by any route of administration, for clozapine-induced hypersalivation. DATA COLLECTION AND ANALYSIS: We extracted data independently. For dichotomous data (homogenous) we calculated relative risk (RR) with 95% confidence intervals (CI) and numbers needed to treat (NNT) on an intention-to-treat basis. We calculated weighted mean difference (WMD) for continuous data. MAIN RESULTS: Of the 15 trials identified, 14 were conducted in China and 14 in hospitals. The quality of reporting was poor with no studies clearly describing allocation concealment and much data were missing or unusable. All results are vulnerable to considerable bias. Most frequently the primary outcome was the diameter of the wet patch on the pillow. Antimuscarinics (astemizole, diphenhydramine, propantheline, doxepin) were the most commonly evaluated drugs. For the outcome of 'no clinically important improvement' astemizole and diphenhydramine were more effective than placebo (astemizole: n=97, 2 RCTs, RR 0.61 CI 0.47 to 0.81 NNT 3 CI 2 to 5; diphenhydramine: n=131, 2 RCTs, RR 0.43 CI 0.31 to 0.58, NNT 2 CI 1.5 to 2.5), but the doses of astemizole used were those that can cause toxicity. Data involving propantheline were heterogeneous (I2= 86.6%), but both studies showed benefit over placebo. Adverse effects were poorly recorded. Of the other interventions, oryzanol (rice bran oil and rice embryo oil extract) showed benefit over the antimuscarinic doxepin in terms of 'no clinically important change' (n=104, 1 RCT, RR 0.45 CI 0.27 to 0.75, NNT 4 CI 2 to 7). The Chinese medicine suo quo wan (comprises spicebush root, Chinese yam and bitter cardamom) showed benefit over doxepin (n=70, 1 RCT, RR 'no clinically important change' 0.31 CI 0.16 to 0.59, NNT 3 CI 1.5 to 3.7). AUTHORS' CONCLUSIONS: There are currently insufficient data to confidently inform clinical practice. The limitations of these studies are plentiful and the risk of bias is high. These trials, however, are invaluable guides for current and future study design. Well conducted randomised trials are possible. Some may be underway. Current practice outside of well designed randomised trials should be clearly justified.

Pica and the elephant's ear.

This is a case report of an otherwise healthy 2-year-old boy with a history of pica, associated with iron deficiency anemia. This boy was referred to our department for a neurologic evaluation because of an acute episode of sialorrhea, difficulty in speaking, dysphagia, and repeated swallowing movements. An uncertain episode of a brief-duration still gaze was also reported. In addition, the history revealed that the child had earlier ingested a leaf from a poisonous houseplant called Colocasia esculenta, also known as "elephant's ear." The habit of pica subsided after treatment with iron supplements. A 9-month follow-up period was uneventful. Neurologic manifestations can accompany accidental intoxications of some non-nutrient substances. Thus, pica must be suspected in children with acute behavior alterations.

[Effect of suo quan pill for reducing clozapine induced salivation].

UNLABELLED: 40 Schizophrenic inpatients with clozapine induced salivation were divided into two groups randomly. They were treated with Suo Quan pill and a control study of the placebo (neutral pill) for reducing clozapine induced salivation. These cases were also classified by TCM Syndrome Differentiation and laboratory examinations were performed. RESULTS: There was a significant difference in effect on salivation between the therapeutic group (21 cases) and the controlled group (19 cases), P < 0.01. According to their TCM subtypes two subtypes (Stagnation of Phlegm-Dampness and Yin Deficiency) showed the best results. No correlation between the peripheral clozapine level and salivation was found. No side effect was recorded.

Acute selenium poisoning of a 2-year-old child.

After ingestion of an unknown amount of a gun blueing compound containing selenious acid (11 ml from the bottle fluid were missing, equivalent to 2.9 g Se) a 2-year-old girl suffered from continuous hyper-salivation, vomiting, diarrhoea, restlessness and muscle spasm. Blood pressure and pulse rate were increased. Symptomatic treatment was performed by parenteral fluid administration. The plasma Se concentration was increased to 20 times normal 5 h after ingestion. Erythrocyte Se exceeded plasma Se, 24 h after intoxication. Urinary Se excretion decreased parallel to the plasma Se concentration. Ten weeks later, the Se content of hair had risen to 10 times normal. The plasma glutathione peroxidase activity showed only a slight increase during the first 36 h, erythrocyte glutathione peroxidase, catalase and superoxide dismutase activities were not significantly altered. The child fully recovered.

Pilot studies in cattle and mice to determine the presence of 4-methylimidazole in milk after oral ingestion.

4-methylimidazole (4-MI) was given orally to a cow in increased dosages to determine if it could be detected in her milk and be present at a concentration high enough to affect her nursing calf. 4-MI was found in the milk, but the calf remained clinically normal throughout the experiment. The cow died after the fourth dose of 20 g 4-MI. Four groups of 10 mice each were given oral doses of water, normal milk, cow's milk after low doses of 4-MI, or cow's milk after high doses of 4-MI. All mice remained healthy after a 2-week feeding trial. Six 3-day-old calves were given 4-MI directly in their bottles of milk up to 2 times the highest level found in toxic feed with only mild depression noted in one calf. Two pregnant cows were given 4-MI pre-partum to determine if it would get into the colostrum at higher levels. Both cows received 4-MI 3 days before they calved and for 2 weeks afterward. Cow A exhibited trembling, excessive salivation and incoordination after the initial dose. Cow B and the newborn calves were never affected throughout the experiment. Each time the dose of 4-MI reached 1.5 g or more, Cow A would exhibit the previously described signs. 4-MI was detected in the colostrum but not in higher concentrations than in the other milk samples.