Central anticholinergic syndrome on therapeutic doses of cyproheptadine

Safety of Cyproheptadine, an Orexigenic Drug. Analysis of the French National Pharmacovigilance Data-Base and Systematic Review

Objectives: Cyproheptadine is a first-generation H1-antihistamine drug first that was distributed in the 1960s. While its orexigenic effect was observed early, cyproheptadine is not yet authorized for this indication in all countries today. There is an increasing medical interest and demand for the orexigenic effect of cyproheptadine, especially in children with poor appetite. As cyproheptadine might be evaluated in future clinical trials, we wanted to assess its safety profile. Methods: Using the French national pharmacovigilance database, we retrospectively analyzed all pediatric and adult reports of adverse effects of cyproheptadine recorded since its first distribution in France. Next, we performed a systematic review of the literature of cyproheptadine adverse effects. Results: Since 1985, 93 adverse effects were reported in the French pharmacovigilance database (adults 81.7%, children 18.3%); these were mainly neurological symptoms (n = 38, adults 71%, children 28.9%), and hepatic complications (n = 15, adults 86.7%, children 13.3%). In the literature, the most frequent adverse effect reported was drowsiness in adults or children, and five case reports noted liver complications in adults. We estimated the frequency of hepatic adverse effects at 0.27 to 1.4/1000, regardless of age. Conclusion: Cyproheptadine can be considered a safe drug. Mild neurological effects appear to be frequent, and hepatotoxicity is uncommon to rare. Randomized controlled trials are needed to evaluate the safety and efficacy of cyproheptadine before authorization for appetite stimulation, especially in young children as studies at this age are lacking. Possible hepatic complications should be monitored, as very rare cases of liver failure have been reported.

Acute Anticholinergic Syndrome from Atropa Belladonna Mistaken for Blueberries

Purpose

To report the first case in the ophthalmic literature of acute anticholinergic syndrome after ingestion of Atropa belladonna mistaken for blueberries.

Methods

A 36-year-old woman presented to our ophthalmic emergency department with complaints of blurry vision, lightning flashes, disorientation, loss of balance, agitation, and anxiety for 24 hours. Ophthalmic examination revealed bilateral pupillary dilatation and paresis of accommodation. Additional symptoms of the anticholinergic syndrome were elicited on further questioning.

Results

Anticholinergic intoxication was suspected and the patient admitted to have eaten six “blueberries” found in the forest the previous day. The patient identified Atropa belladonna as the source of the berries she had eaten when shown photographs of the plant and its fruit. The recommendations of the Swiss Toxicological Information Centre were followed and physostigmine, the antidote for severe poisoning when 10 or more berries are ingested, was not administered.

Conclusions

Accidental ingestion of Atropa belladonna berries may cause patients to first consult an ophthalmologist. It is important to recognize the anticholinergic syndrome caused by such intoxication in order to make a proper diagnosis, avoid unnecessary testing, and provide expedient appropriate treatment when required.

When Too Much Is Enough: Pediatric Cyproheptadine Overdose with Confirmatory Level

Cyproheptadine is an H-1 antihistamine with anticholinergic and antiserotonergic effects. Cyproheptadine’s most common use has been in the management cold-induced urticaria. It is often used in primary care for its side effect of appetite stimulation. Recently there has been increasing interest in its use in the treatment of drug-induced serotonin syndrome. Cyproheptadine overdose is uncommonly reported in the medical literature. We report the rare case of a pediatric cyproheptadine overdose with a confirmatory cyproheptadine level.

Cyproheptadine Use in Children With Functional Gastrointestinal Disorders

OBJECTIVE

The objective of this study was to evaluate clinical improvement and safety with use of cyproheptadine in functional gastrointestinal disorders (FGIDs) in children.

METHODS

Retrospectively evaluating the efficacy and safety of the use for indications including Rome III-defined FGIDs: functional abdominal pain, functional dyspepsia, irritable bowel syndrome (IBS), abdominal migraine, cyclic vomiting syndrome. Response categories were as follows: no improvement group/partial improvement group; requiring intervention, or complete improvement group (CIG); warranting discontinuation; ongoing use; or parental unwillingness to stop medication.

RESULTS

Among 307 patients, 151 included; 58% girls, ages 1 to 18 years (median 9); 110 (72.8%) reported complete symptom improvement; 41 (27.2%) reported no or partial improvement. Mean initial and final doses in the CIG were 4.85 mg/day (0.14 mg · kg · day) and 5.34 mg/day (0.14 mg · kg · day), respectively. A total of 102/151 (68%) reported no adverse effects. Adverse effects shown were as sleepiness in 19/151 (13%) and weight gain in 15/151 (10%). Cyproheptadine was effective in improving symptoms of functional abdominal pain, functional dyspepsia, in a relatively larger number of patients. Patients in smaller numbers had significant improvement 13/18 (72%) abdominal migraine, 10/10 (100%) IBS, and 6/8 (75%) cyclic vomiting syndrome. This is the first time report of improvement in IBS. Other pharmacodynamics had been as follows: the lower the body weight, the higher are the odds of no to partial improvement; patients in no improvement group/partial improvement group experience more adverse effects as compared to the CIG; the single best predictor of clinical improvement was body mass index. A 1 unit increase in body mass index with cyproheptadine use increased the odds of clinical improvement by 1.5-fold (P = 0.01).

CONCLUSIONS

Cyproheptadine effectively improves symptoms of Rome III-defined FGIDs and has a good safety profile when used for these indications.

Serotonergic or Anticholinergic Toxidrome: Case Report of a 9-Year-Old Girl

OBJECTIVE

The aim of this study was to report an acute onset of symptoms erroneously attributed to serotonin syndrome in a child who had been given both anticholinergic and serotonergic agents.

CASE SUMMARY

A 9-year-old girl with chronic anxiety and gastrointestinal problems was prescribed oral sertraline 6.25 mg daily, as well as hyoscyamine, ondansetron, montelukast, and a course of nitazoxanide. She was also routinely given diphenhydramine and omeprazole. Three days after increasing sertraline to 12.5 mg, she presented to the emergency department with altered mental status, hallucinations, mydriasis, tachycardia, and pyrexia. She was admitted to the pediatric intensive care unit and subsequently treated unsuccessfully for serotonin syndrome, with blurred vision and clonus persisting at discharge 4 days after admittance. Upon follow-up with her outpatient clinic, all anticholinergic agents were discontinued, and symptoms slowly resolved.

CONCLUSIONS

This case illustrates the importance of differential diagnosis between toxidromes and how clinical presentation can be altered by preexisting conditions as well as the use of medications that affect multiple neurotransmitter systems.

The antidepressant 5-HT2A receptor antagonists pizotifen and cyproheptadine inhibit serotonin-enhanced platelet function

There is considerable interest in defining new agents or targets for antithrombotic purposes. The 5-HT_2A receptor is a G-protein coupled receptor (GPCR) expressed on many cell types, and a known therapeutic target for many disease states. This serotonin receptor is also known to regulate platelet function. Thus, in our FDA-approved drug repurposing efforts, we investigated the antiplatelet activity of cyproheptadine and pizotifen, two antidepressant 5-HT_2A Receptor antagonists. Our results revealed that cyproheptadine and pizotifen reversed serotonin-enhanced ADP-induced platelet aggregation in vitro and ex vivo. And the inhibitory effects of these two agents were found to be similar to that of EMD 281014, a 5-HT_2A Receptor antagonist under development. In separate experiments, our studies revealed that these 5-HT_2A receptor antagonists have the capacity to reduce serotonin-enhanced ADP-induced elevation in intracellular calcium levels and tyrosine phosphorylation. Using flow cytometry, we also observed that cyproheptadine, pizotifen, and EMD 281014 inhibited serotonin-enhanced ADP-induced phosphatidylserine (PS) exposure, P-selectin expression, and glycoprotein IIb-IIIa activation. Furthermore, using a carotid artery thrombosis model, these agents prolonged the time for thrombotic occlusion in mice in vivo. Finally, the tail-bleeding time was investigated to assess the effect of cyproheptadine and pizotifen on hemostasis. Our findings indicated prolonged bleeding time in both cyproheptadine- and pizotifen-treated mice. Notably, the increases in occlusion and bleeding times associated with these two agents were comparable to that of EMD 281014, and to clopidogrel, a commonly used antiplatelet drug, again, in a fashion comparable to clopidogrel and EMD 281014. Collectively, our data indicate that the antidepressant 5-HT_2A antagonists, cyproheptadine and pizotifen do exert antiplatelet and thromboprotective effects, but similar to clopidogrel and EMD 281014, their use may interfere with normal hemostasis.

Effect of cyproheptadine on serum leptin levels

Leptin is a 167 amino acid protein encoded by the obesity gene that is synthesized in adipose tissue and interacts with receptors in the hypothalamus linked to the regulation of appetite and metabolism. It is known to suppress appetite and increase energy expenditure. Cyproheptadine is a piperidine antihistamine that increases appetite through its antiserotonergic effect on 5-HT2 receptors in the brain. Although both leptin and cyproheptadine are effective in controlling appetite, their interaction has not been addressed in clinical studies. This study evaluated serum leptin concentrations in patients who received cyproheptadine to treat a variety of disorders. Sixteen patients aged 7 to 71 years (mean, 26.25 years) were given cyproheptadine 2 to 6 mg/day for a minimum of 7 days. Body weight was measured and blood samples were obtained at baseline and after 1 week of treatment. Serum leptin levels were determined by leptin radioimmunoassay. The mean body weight at baseline (52.59 kg) did not differ significantly from that at 1 week after treatment (52.84 kg; P > .05), but the mean leptin level after 1 week of treatment with cyproheptadine (3.14 ng/mL) was 14.2% higher than that at baseline (2.75 ng/mL; P < .05). This increase may suggest that both leptin and cyproheptadine may affect appetite via similar receptors and that cyproheptadine does not impair leptin activity through these receptors. Further study will be necessary to clarify this relationship.

Antihistamines in Dermatology

Along with antibiotics, antihistamines are the most widely used systemic drugs in dermatology. This is attributable to the major role played by histamine in common diseases such as urticaria and atopic eczema. Of the currently recognised four subtypes of G protein-coupled histamine receptors, only the H1 and H2 subtypes have been positively identified in human skin. Traditionally believed to be competitive antagonists of histamine, H1 and H2 antihistamines are now considered to behave as inverse agonists. By consensus, H1 antihistamines are classified as 'first generation' (associated with troublesome side-effects including somnolence, anti-adrenergic and atropine-like actions) and 'second-generation' compounds (in which these side-effects are reduced or absent). The main indications for H1 antihistamines in skin are suppression of pruritus in urticaria and atopic eczema, both of which are associated with increased mast cell numbers and tissue histamine levels. However the evidence basis for use in atopic eczema is ambiguous and controversial, even though these drugs are widely used in practice. Currently, significant side-effects are mainly confined to the first-generation compounds and are especially troublesome in the elderly. Psychomotor impairment may persist throughout the day following administration. Anti-cholinergic and anti-alpha-adrenergic blockade and cardiotoxicity (torsade de pointes) may also occur with first-generation antihistamines. Two early low-sedation second-generation antihistamines caused arrhythmias in a small number of patients but these compounds have now been withdrawn. Generally, the second-generation H1 antihistamines are well tolerated.

Hallucinatory experiences in a community sample of Japanese children

OBJECTIVE

Hallucinatory experiences in children are often thought to indicate serious psychopathology. However, they have also been reported in normally developing children and in association with temporary psychological reactions to acute stress. The aim of this study was to investigate the prevalence of hallucinatory experiences in a nonclinical population of children and to examine the relationship between the modality and content of hallucinations and psychopathology.

METHOD

Seven hundred sixty-one Japanese children, 11 to 12 years old, completed a battery of four measures: (1) a questionnaire about the type of hallucinatory experience, (2) the Children's Depression Inventory, (3) the State-Trait Anxiety Inventory for Children, and (4) the Adolescent Dissociative Experiences Scale.

RESULTS

Approximately 21% of the subjects had experienced hallucinations. Subjects who had experienced hallucinations, in particular, hallucinations characterized by combined modalities, closely self-related auditory content, or concrete visual content, had more significant psychopathology than did those who had never experienced hallucinations.

CONCLUSIONS

Therapeutic intervention should be considered for children who experience hallucinations in association with depression, anxiety, or dissociation.

Adverse effects associated with physical restraint

OBJECTIVE

Restraint use is not monitored in the US, and only institutions that choose to do so collect statistics. In 1999, investigative journalists reported lethal consequences proximal to restraint use, making it a life-and-death matter that demands attention from professionals. This paper reviews the literature concerning actual and potential causes of deaths proximal to the use of physical restraint.

METHOD

Searching the electronic databases Medline, Cinahl, and PsycINFO, we reviewed the areas of forensics and pathology, nursing, cardiology, immunology, psychology, neurosciences, psychiatry, emergency medicine, and sports medicine.

CONCLUSIONS

Research is needed to provide clinicians with data on the risk factors and adverse effects associated with restraint use, as well as data on procedures that will lead to reduced use. Research is needed to determine what individual risk factors and combinations thereof contribute to injury and death.

A female with central anticholinergic syndrome responsive to neostigmine

Central anticholinergic syndrome is a rarely observed condition in children. The occurrence of this syndrome after ingestion of Solanum pseudocapsicum is infrequent because findings tend to be milder and localized to the gastrointestinal system, without central nervous system involvement. Most patients do not present with diagnostic problems because their relatives can usually report any ingestion of poisonous agents; however, when drug poisoning or plant ingestion is uncertain, a differential diagnosis with encephalitis must be considered. Physostigmine salicylate is the specific antidote because it crosses the blood-brain barrier because of its tertiary ammonium group. Neostigmine methylsulfate has a quaternary ammonium group, which prevents its penetration through the blood-brain barrier; hence its primary influence is believed to be due to its action on the peripheral nervous system. We describe a female with central anticholinergic syndrome caused by ingestion of Solanum pseudocapsicum. A slow intravenous infusion of neostigmine methylsulfate (0.03 mg/kg) immediately resolved the clinical picture. To our knowledge, this case is the first reported of central anticholinergic syndrome occurring after ingestion of Solanum pseudocapsicum in a child and the first report of a complete and rapid remission after intravenous neostigmine methylsulfate administration.

Update on medications used to treat gastrointestinal disease in children

Progress in the pharmacotherapy of pediatric gastrointestinal diseases continued during 1998 despite ongoing obstacles encountered by clinicians and researchers. The major change involved warnings that cisapride, a widely used prokinetic agent, could cause potentially fatal arrythmias in susceptible people. The risk for children is unclear and a consensus of prescribing guidelines is needed. Excellent pediatric-oriented reviews have been published that summarize our knowledge of proton pump inhibitors, probiotics, 5-hydroxtryptamine-3 (5-HT3) antagonists, and the treatment of gastrointestinal infections and chronic abdominal pain. Triple medication therapy for the eradication of Helicobacter pylori is now the standard of care, but the optimal combination and duration of therapy needs to be determined. Also described are interesting developments requiring further confirmation: the treatments of infectious diarrhea with zinc; achalasia and Hirschsprung's disease with botulinum toxin; weight loss with megestrol acetate; and sialorrhea with glycopyrollate.