Cholinergic symptoms and QTc prolongation following donepezil overdose.

Donepezil is the most commonly prescribed acetylcholinesterase inhibitor for the treatment of Alzheimer's disease, an ailment that affects millions of older adult patients. By inhibiting the breakdown of acetylcholine in the central nervous system, donepezil has been shown to slow cognitive decline and improve patients' functional status. While donepezil is well-tolerated and generally considered safe at therapeutic doses, taking more than the prescribed dose could result in adverse cholinergic effects that range from mild gastrointestinal distress to serious cardiac dysrhythmias. We present a case of an 84-year-old man who developed gastrointestinal and cardiac disturbances after ingesting seven-times his daily dose of donepezil. As no specific antidote is available for donepezil overdose, this case highlights the importance of supportive care with particular attention to the management of cardiac dysrhythmias in patients displaying signs of toxicity.

An autopsy case of death by combined use of benzodiazepines and diphenidine.

We present an autopsy case involving benzodiazepines and diphenidine. Quantitative toxicological analysis showed concentrations of 7-aminoflunitrazepam (a flunitrazepam metabolite), 7-aminonimetazepam (a nimetazepam metabolite), chlorpheniramine and diphenidine in femoral blood of 0.086 µg/ml, 0.027 µg/ml, 0.066 µg/ml, and 0.073 µg/ml, respectively. Death was attributed to combined toxicity due to the influence of multiple drug interactions.

Fatal diphenidol poisoning: a case report and a retrospective study of 16 cases.

Diphenidol hydrochloride (DPN), a nonphenothiazinic antiemetic agent used primarily in patients with Meniere disease and labyrinthopathies to treat vomiting and vertigo, is considered to be a relatively safe drug. Since it was first approved in the United States in 1967, this drug has been widely used in Latin America and Asia and has contributed to sporadic suicidal and accidental poisonings in mainland China and Taiwan. However, its toxic or lethal concentration ranges have not yet been determined. We report a case of a 23-year-old female who suffered from DPN poisoning that resulted in death. At autopsy, there were no typical pathological findings, except for cerebral edema with high acetylcholinesterase expression. Postmortem analysis of DPN revealed 45 µg/ml in heart blood, 39 µg/ml in femoral vein blood, 141 µg/g in the liver, and 53 mg in the gastric contents. These concentrations indicated that the cause of death was DPN poisoning. The circumstances indicated that the manner of death was suicide. We also present a retrospective study, in which we review and summarize the literature from 1998 to 2014 and describe 16 cases of poisoning, including information from autopsy reports and postmortem drug concentrations. In forensic practice, drug residues at the scene, patients with convulsions and disturbance of consciousness, and rapidly occurring deaths, should draw attention to the possibility of this drug. Toxicological analysis and the exclusion of other diseases may ultimately be used to confirm DPN poisoning.

Encephalopathy from unintentional donepezil and memantine ingestion.

Donepezil and memantine are commonly prescribed antidementia drugs. There is a paucity of literature concerning pediatric ingestions of these drugs. We describe a case of a 2-year-old child who developed encephalopathy after an unintentional ingestion of donepezil and memantine. A 2-year-old girl was found by her family members agitated and reporting visual hallucinations. In the emergency department, she became sedated and had rightward eye deviation. She was hospitalized and had extensive neurological and infectious disease testing that was unremarkable, except for an electroencephalogram, which showed a nonspecific encephalopathy. She recovered with supportive care for 72 hours. Serum concentrations of donepezil and memantine measured on arrival were 470 ng/mL (therapeutic range, 25-50 ng/mL) and 32 ng/mL (therapeutic range, 70-150 ng/mL), respectively. This case demonstrates that unintentional ingestions of memantine and donepezil can potentially cause significant and prolonged neurological symptoms in pediatric patients.

[Coniin, in Five Little Pigs].

In this manuscript, I provide some insights into the novel Five Little Pigs (US title: Murder in Retrospect) by Agatha Christie, and overview the neurotoxin coniine that plays an essential role in that story. Coniine is a nicotinic acetylcholine receptor antagonist, and induces a slowly spreading effect of paralysis by acting directly on the peripheral nervous system. This agent has been used as a poison for thousands of years; indeed, the philosophical text Phaedo describes that coniine was used to put Socrates to death. Based on this background, Christie's views on human nature and her creative powers are also discussed.

Effects of the antitussive drug cloperastine on ventricular repolarization in halothane-anesthetized guinea pigs.

Cloperastine is an antitussive drug, which can be received as an over-the-counter cold medicine. The chemical structure of cloperastine is quite similar to that of the antihistamine drug diphenhydramine, which is reported to inhibit hERG K⁺ channels and clinically induce long QT syndrome after overdose. To analyze its proarrhythmic potential, we compared effects of cloperastine and diphenhydramine on the hERG K⁺ channels expressed in HEK293 cells. We further assessed their effects on the halothane-anesthetized guinea-pig heart under the monitoring of monophasic action potential (MAP) of the ventricle. Cloperastine inhibited the hERG K⁺ currents in a concentration-dependent manner with an IC50 value of 0.027 µM, whose potency was 100 times greater than that of diphenhydramine (IC50; 2.7 µM). In the anesthetized guinea pigs, cloperastine at a therapeutic dose of 1 mg/kg prolonged the QT interval and MAP duration without affecting PR interval or QRS width. Diphenhydramine at a therapeutic dose of 10 mg/kg prolonged the QT interval and MAP duration together with increase in PR interval and QRS width. The present results suggest that cloperastine may be categorized as a QT-prolonging drug that possibly induces arrhythmia at overdoses like diphenhydramine does.

[Rhabdomyolysis: have you considered food poisoning from quails?]

Rhabdomyolysis (R) is a complex condition involving the rapid dissolution of damaged or injured skeletal muscle. This leads to the direct release of intracellular components, including myoglobin, creatine kinase, aldolase, and lactate dehydrogenase, as well as electrolytes, into the bloodstream and extracellular space. Clinically, R shows a triad of symptoms: myalgia, limb weakness, and myoglobinuria without hematuria, while myoglobin has been recognized as playing a part in the development of acute kidney injury. Coturnism is a relatively rare disease, mostly found in the European countries bordering the Mediterranean Sea, characterized by acute R. It follows the consumption of Coturnix coturnix, a species of quails common in Europe, that have ingested the toxic substances (and especially coniine) present in the herbaceous plant called hemlock (Conium maculatum). Coniine may be lethal at a dose of 150 mg but it has neurotoxic effects at smaller doses, with acute R and acute kidney injury. Freezing and cooking the meat does not inactivate the alkaloids present in the birds' flesh and digestive tract. The clinical course of coturnism includes neurotoxicosis, tremor, vomiting, muscle paralysis, respiratory paralysis/failure, R and acute kidney injury. In appropriate geographical and temporal settings, it should be considered when diagnosing patients with acute R. The genetic, biochemical and epidemiological characteristics of coturnism are not yet fully known, while we wait reliable data from experimental studies.

Asenapine, iloperidone and lurasidone exposures in young children reported to U.S. poison centers.

CONTEXT: Asenapine, iloperidone and lurasidone are relatively new atypical antipsychotics. There is limited information on toxicity on pediatric exposures to these drugs. The objective of this study was to compare toxicity associated with asenapine, iloperidone and lurasidone exposures in young children. METHODS: A retrospective study of U.S. National Poison Data System from 2010 to 2015 of single substance exposures to asenapine, iloperidone or lurasidone in children <6 years of age that were followed to known outcome was performed. RESULTS: There were 95 asenapine, 64 iloperidone and 124 lurasidone cases that met inclusion criteria. Reason was exploratory for 96% of cases. Drowsiness/lethargy occurred most frequently with iloperidone (45%) and least often with lurasidone (8%). Two iloperidone cases had respiratory depression. For asenapine, iloperidone and lurasidone, respectively, management sites were on-site non-health care facility (non-HCF) (32%, 16%, 26%), treated/discharged from emergency department (ED) (46%, 47%, 63%), admitted to noncritical care (9%, 14%, 10%) and admitted to critical care (10%, 22%, 2%). Clinical effect duration was 8 h or less for the majority of non-HCF cases (80%) and for children treated/discharged from the ED (72%). For asenapine, iloperidone and lurasidone, coded outcomes were no effect (50%, 41%, 81%), minor effect (43%, 39%, 17%), moderate (6%, 19%, 2%) and major (0, 2%, 0). DISCUSSION AND CONCLUSIONS: These findings suggest that in children under 6 years of age, lurasidone exposures were least serious and iloperidone exposures were most serious based on clinical effects, management sites and coded outcomes. Observation of symptomatic children in the ED for 8 h should be sufficient to make triage decisions based on persistence or resolution of clinical effects.

Neurotoxicity of Prosopis juliflora: from Natural Poisoning to Mechanism of Action of Its Piperidine Alkaloids.

Prosopis juliflora was introduced in northeastern Brazil in the 1940s, and since then, it has been available as an alternative for animal nutrition. However, the consumption of P. juliflora as main or sole source of food causes an illness in animals known locally as "cara torta" disease. Cattle and goats experimentally intoxicated presents neurotoxic damage in the central nervous system. Histologic lesions were mainly characterized by vacuolation and loss of neurons in trigeminal motor nuclei. Furthermore, mitochondrial damage in neurons and gliosis was reported in trigeminal nuclei of intoxicated cattle. Studies, using neural cell cultures, have reproduced the main cellular alterations visualized in cara torta disease and contributed to understanding the mechanism of action piperidine alkaloids, the main neurotoxic compound in P. juliflora leaves and pods. Here, we will present aspects of the biological and toxicological properties of P. juliflora and its pharmacologically active compounds.

[Desoxypipradrol - a new (already well known) designer drug]. / Desoxypipradrol - eine neue (alte) Designerdroge.

Novel psychoactive substances (NPS) are easily accessible and the consumption has increased in recent years. New compounds as well as compounds derived from pharmaceutical research or the patent literature are provided, mostly without any declaration. As a consequence, severe adverse reactions may occur after consumption of unknown doses of these drugs, in particular after mixed intake of different psychoactive substances or co-medication. The toxic effects in such cases are not predictable. We report cases of rhabdomyolysis in patients after consumption of desoxipipradrol in combination with other NPS. Particularly in case of synergistic serotonergic effects a distinct stimulation of 5-HT2A-receptors (or 5-HT1A-receptors) should be considered which may lead to serotonergic syndrome.

Prolonged hypoglycemia after a suicidal ingestion of repaglinide with unexpected slow plasma elimination.

CONTEXT: Repaglinide is a short-acting insulin secretagogue with high interindividual variability in pharmacokinetics due to genetic polymorphisms. Little is known about repaglinide overdoses, both with respect to pharmacokinetics and appropriate management. Given its short serum half-life of less than 1 h, hypoglycemic effects of repaglinide are expected to cease within a few hours post-ingestion. CASE DETAILS: A 15-year-old girl ingested 10.5 mg of repaglinide in a suicide attempt. Few hours later, she developed a strong food craving, nausea, abdominal pain, and a headache. The lowest recorded serum glucose was 44 mg/dl (2.4 mmol/l) 14 h post-ingestion. Using liquid chromatography-mass spectrometry, we detected repaglinide serum levels of 5.3, 2.6, and 1.0 ng/ml at 14, 20, and 26 h post-ingestion, respectively. DISCUSSION: This case illustrates that in the context of overdose, repaglinide can lead to prolonged hypoglycemia. We therefore recommend glucose monitoring and observation for 24 h in all patients who remain hypoglycemic or show symptoms of hypoglycemia for an unusually long period of time.

First reported fatalities associated with the 'research chemical' 2-methoxydiphenidine.

2-Methoxydiphenidine, i.e. 1-[1-(2-methoxyphenyl)-2-phenylethyl]piperidine, also known as 'MXP' or '2-MeO-diphenidine' (or 2-MXP), has been available as a 'research chemical' since 2013 as a purported alternative to the 'dissociative anesthetics' methoxetamine and ketamine. Three deaths which involved the detection of 2-MXP in post-mortem blood and urine were encountered in forensic casework. The 2-, 3- and 4-methoxyphenyl positional isomers were synthesized to confirm the identity and concentration of 2-MXP. The 2-MXP femoral blood concentrations in the cases were found to be 24.0, 2.0 and 1.36 mg/L (the latter with an alternative cause of death). Some additional prescription drugs were encountered at therapeutic concentrations in all three cases. Analysis of the biofluids allowed the detection and characterization of various metabolites, including the suggested presence of hydroxy-2-MXP as the main metabolite with the hydroxyl group located on the piperidine rather than the phenyl or benzyl moiety. Additional metabolites included O-desmethyl-2-MXP and hydroxylated O-desmethyl-2-MXP. Diphenidine and hydroxy-diphenidine, also showing the presence of the hydroxyl group on the piperidine ring, were also detected. It was not possible to identify whether these arose from 2-MXP biotransformation or whether they represented the presence of diphenidine as a separate substance. These are the first published fatalities involving 2-MXP and presents analytical data to assist analytical toxicologists with future casework.

A fatal case of poisoning related to new cathinone designer drugs, 4-methoxy PV8, PV9, and 4-methoxy PV9, and a dissociative agent, diphenidine.

A woman in her thirties was found dead on a bed. Considerable amounts of "aroma liquid" and "bath salt" products and hypnotic drug tablets were scattered beside the bed. Autopsy showed pulmonary congestion and edema. Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) analyses of "aroma liquid" and "bath salt" products showed the presence of new cathinone designer drugs, 4-methoxy PV8 (4-methoxy PHPP), PV9 (α-POP), and 4-methoxy PV9 (4-methoxy α-POP), and a dissociative agent, diphenidine. Drug screening in stomach contents, blood and hydrolyzed urine of the woman by GC-MS and liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed the presence of the above 4 types of drugs and 3 types of benzodiazepines, triazolam, flunitrazepam, and nitrazepam, and their metabolites. The above 7 drugs and 3 benzodiazepine metabolites were simultaneously determined by LC-MS/MS after modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) extraction using diazepam-d5 as the internal standard. The concentrations of 4-methoxy PV8, PV9, 4-methoxy PV9, and diphenidine in the femoral blood were 2.69, 0.743, 0.261, and 1.38µg/ml, respectively, which were significantly higher than concentrations reported in previous cases. Alcohol concentration in the femoral blood was 1.52mg/ml. Based on the pathological and toxicological findings, the cause of death was determined to be 3 types of cathinone drugs, 4-methoxy PV8, PV9, and 4-methoxy PV9, and diphenidine poisoning under the influence of 3 benzodiazepines and alcohol.

Intoxications by the dissociative new psychoactive substances diphenidine and methoxphenidine.

BACKGROUND: Diphenidine (1-(1,2-diphenylethyl)piperidine) and its 2-methoxylated derivative methoxphenidine (MXP, 2-MeO-diphenidine) are substances with dissociative effects that were recently introduced for "recreational" purpose through the online-based sale of new psychoactive substances (NPS). A number of analytically confirmed non-fatal intoxications associated with diphenidine or MXP have occurred in Sweden and were included in the STRIDA project. STUDY DESIGN: Observational case series of consecutive patients with admitted or suspected intake of NPS and requiring intensive treatment in an emergency room and hospitalization in Sweden. PATIENTS AND METHODS: Blood and urine samples were collected from intoxicated patients presenting at emergency departments all over the country. NPS analysis was performed by multi-component liquid chromatography-mass spectrometry methods. Data on clinical features were collected during telephone consultations with the Poisons Information Centre and retrieved from medical records. Information was also obtained from online drug discussion forums. CASE SERIES: Over a 12-month period from January to December 2014, 750 cases of suspected NPS intoxication originating from emergency departments were enrolled in the STRIDA project of which 14 (1.9%) tested positive for diphenidine and 3 (0.4%) tested positive for MXP. Co-exposure to several other NPS (e.g., 5-/6-(2-aminopropyl)benzofuran, 2-4-bromomethcathinone, butylone, 3,4-dichloromethylphenidate, 5-methoxy-N-isopropyltryptamine, methiopropamine, and α-pyrrolidinopentiothiophenone), also including other dissociative substances (3-/4-methoxyphencyclidine), and classical drugs of abuse (e.g., cannabis and ethanol) was documented in 87% of these cases. The 17 patients were aged 20-48 (median: 32) years, and 13 (76%) were men. They commonly presented with hypertension (76%), tachycardia (47%), anxiety (65%), and altered mental status (65%) including confusion, disorientation, dissociation, and/or hallucinations. Eight patients (47%) displayed severe intoxication (Poisoning Severity Score 3). The diphenidine- or MXP-positive patients required hospitalization for 1-3 (median: 2) days. In addition to standard supportive therapy, half of the cases were treated with benzodiazepines and/or propofol. CONCLUSION: The adverse effects noted in analytically confirmed cases of NPS intoxication involving diphenidine or MXP were similar to those reported for other dissociative substances such as ketamine and methoxetamine. However, the high proportion of polysubstance use might have played a role in the intoxication and clinical features in some cases.

Lesions of amygdala, pyriform cortex and other brain structures due to dipiperidinoethane intoxication.

Single doses of dipiperidinoethane (DPE) produced symmetrical necrosis in pyriform cortex, amygdala and other areas of gray matter in rats, mice and gerbils. The necrosis was detectable in 10 hours and fully developed in 24 hours. Its distribution and severity were not influenced by carotid artery ligation. DPE was not a cumulative poison. There was a high degree of chemical specificity: neurotoxic activity was present in DPE derivatives modified by methylation of the two piperidine rings, but neurotoxicity was absent in derivatives with different ring systems or different connecting chains.

Repaglinide-induced factitious hypoglycemia.

We report the first case of repaglinide-induced factitious hypoglycemia in a young male. This case posed a challenging diagnostic dilemma because commercial assays for repaglinide are not available. Furthermore, the patient had a series of positive diagnostic tests such as high proinsulin and localizing intra-arterial calcium stimulation suggestive of insulinoma. This case, again, demonstrates the importance of pure clinical judgment in the face of often-conflicting laboratory data in making a correct diagnosis and the requirement of definitive data for an appropriate therapeutic resolution.

The industrial chemical Tinuvin 123 does not induce dopaminergic neurotoxicity in C57Bl/6 mice.

We have investigated the acute effects of systemic administration of Tinuvin 123 on nigro-striatal dopaminergic neurons in the C57Bl/6 mouse. Tinuvin 123 was administered subcutaneously (s.c.) twice, 16 h apart, at doses of 0, 2, 20 or 200 mg/kg body weight to a total of 48 male C57Bl/6 mice (12 animals/group). Seven days following the last dose the animals were decapitated and the brains removed. No deaths occurred during the study. There were no differences between the mean body weights of any of the experimental groups prior to or following Tinuvin 123 treatment. Animals treated s.c. with 2 mg/kg Tinuvin 123 exhibited no changes in striatal dopamine or metabolite concentrations compared with vehicle-treated animals. Higher doses of Tinuvin 123 (20 and 200 mg/kg) resulted in a moderate loss of striatal dopamine (31 and 38%) but concentrations of the dopamine metabolites 3,4-dihydroxyphenylacetic acid and homovanillic acid and the neurotransmitters serotonin, aspartate, gamma aminobutyric acid and glutamate were unchanged. The total number of tyrosine hydroxylase-immunoreactive neurons in the entire substantia nigra were equivalent in the vehicle- and Tinuvin 123-treated animals at all doses, thus no neuronal loss was demonstrated. In conclusion, this study demonstrates no evidence that systemic administered Tinuvin 123 induces dopaminergic neurotoxicity in C57Bl/6 mice.