Methamidophos poisoning: A paediatric case report.

Methamidophos is a highly hazardous organophosphate and is known to cause an acute cholinergic toxidrome. Methamidophos use is not allowed in South Africa and therefore local data pertaining to methamidophos poisoning is very limited, with no paediatric clinical cases described. Methamidophos is an active metabolite of acephate, a commonly used organophosphate, registered for agricultural use in South Africa. We present a paediatric case of methamidophos poisoning with prolonged clinical effects. The patient experienced a prolonged cholinergic toxidrome lasting 10 days, with a period of near-full recovery during this time. We discuss the biological plausibility of the detected methamidophos being a byproduct of acephate. In addition, we highlight the importance of closer monitoring of patients with organophosphate poisoning in areas where acephate is commonly used.

Mining and analysis of ADE signals of two camptothecin topoisomerase 1 inhibitors / 中国药房

OBJECTIVE To mine and analyze the adverse drug events （ADE） signals of two camptothecin topoisomerase 1 inhibitors， i.e. irinotecan and topotecan， and to provide reference for clinical medication safety. METHODS Based on the U.S. Food and Drug Administration Adverse Event Reporting System （FAERS） database， ADE report data for the aforementioned two drugs were extracted from January 1， 2004 to March 31， 2023. After processing the data， signal mining was conducted by using the reporting odds ratio in conjunction with the Bayesian confidence propagation neural network， followed by analysis. RESULTS A total of 14 738 relevant ADE reports were screened， among which 11 483 were associated with irinotecan and 3 255 with topotecan. The ADE reports for irinotecan were predominantly male， whereas for topotecan， they were predominantly female； the age of patients using the two drugs mainly concentrated in 45-＜75 years old. A total of 847 signals were detected， involving 24 system organ classes （SOCs）. Among them， 565 signals of irinotecan were detected， involving 24 SOCs， primarily concentrating on gastrointestinal disorders， general disorders and administration site conditions， blood and lymphatic system disorders； the most frequently reported ADE was diarrhea， and the ADE with the strongest signal intensity was cholinergic syndrome. A total of 282 signals of topotecan were detected， involving 22 SOCs， primarily concentrating on general disorders and administration site conditions， investigations， blood and lymphatic system disorders， and gastrointestinal disorders； the most frequently reported ADEs were death and anemia， and the ADE with the strongest signal intensity was febrile bone marrow aplasia. ADE signals for irinotecan such as metastatic colorectal cancer， peripheral sensory neuropathy， steatohepatitis， and those for topotecan such as iris atrophy， retinal degeneration， vitreous hemorrhage， were not documented in their respective drug instruction. CONCLUSIONS ADEs of irinotecan and topotecan primarily involve the digestive and hematologic systems， warranting close clinical monitoring. Cholinergic syndrome caused by irinotecan should be concerned. In addition， patients receiving irinotecan should also be monitored for ADE such as metastatic colorectal cancer， peripheral sensory neuropathy， steatohepatitis， and proteinuria； for patients using topotecan， enhanced surveillance of ocular diseases is recommended to ensure medication safety.

"Cholinergic side Effect-Free anticancer drugs: paving the way for safer and more effective cancer treatment".

Cancer is a leading cause of mortality worldwide, and various anticancer medications have been developed that target different biological pathways involved in cancer growth and progression. Topoisomerase 1 (Top1) is an essential enzyme involved in unwinding supercoiled DNA, and it serves as a key target for several anti-cancer drugs. Irinotecan (FDA approved drug), a semi-synthetic camptothecin derivative, is an effective Top1 toxin that eliminates human cancer cells. Cancer patients suffer from the cholinergic syndrome caused by irinotecan and other Top1 inhibitors. Irinotecan-treated patients have developed cholinergic syndrome due to acetylcholinesterase (AChE) enzyme inhibition. It appears that irinotecan or its metabolites directly interact with AChE and inhibit its role of converting acetylcholine to choline, leading to an accumulation of acetylcholine and subsequent symptoms of the cholinergic syndrome. The phytochemicals present in Phyllanthus emblica, commonly referred to as amla, have been studied to determine their therapeutic effects. As an alternative treatment for cancer, this study explores the potential of phytochemicals found in amla to target and inhibit the Top1 protein. Additionally, the study aims to identify a non-inhibitor for AChE. Molecular docking studies assessed phytochemical binding affinities to Top1 and AChE enzymes, and ADME analyses were performed to assess their drug-likeness properties. Subsequently, molecular dynamic simulation was employed to assess the stability of these compounds. The results suggest that new anticancer medications that do not inhibit AChE or fresh Top1 inhibitors that use the camptothecin scaffold may alleviate some of the irinotecan's side effects.Communicated by Ramaswamy H. Sarma.

Case report: Serotoninergic and cholinergic syndromes induced by self-medication.

Self-medication is a part of the self-care practices carried out by the elderly in their environment. The aim of this case report is to show how the self-medication of fluoxetine and dimenhydrinate in an older adult can induce serotoninergic and cholinergic syndromes, showing symptoms such as nausea, tachycardia, tremor, loss of appetite, memory loss, decreased vision, falls, and increased urination. An older adult who has been diagnosed with arterial hypertension, dyslipidemia, diabetes mellitus, and a recent diagnosis of essential thrombosis is the subject of this case report. After the analysis of the case, cessation of fluoxetine was recommended to avoid withdrawal symptoms, therefore decreasing the need for dimenhydrinate and the medicines used for dyspepsia. After the recommendation, the patient showed an improvement in the symptoms. Finally, the comprehensive evaluation process of the medication in the Medicines Optimization Unit achieved the detection of the problem and improved the patient's health condition.

Recognition and Treatment Challenges of Acute Clozapine Withdrawal Syndrome: A Case Report.

The limited psychiatric bedspace due to the COVID-19 pandemic and the lack of access to an up-to-date medication regimen delayed the recognition of the diagnosis and treatment for a 40-year-old man with schizoaffective disorder, bipolar type, who traveled from his home city and abruptly discontinued his prescription of clozapine. He developed a cholinergic rebound syndrome including delirium and extrapyramidal symptoms (EPS). The delay included time spent in two different medical hospitals: one awaiting psychiatric bedspace, and secondly, when the patient's cholinergic rebound syndrome was misdiagnosed as acute alcohol withdrawal. Once the etiology was recognized, he was promptly treated with anticholinergic medication (benztropine) and retitrated to his outpatient dose of clozapine leading to the resolution of symptoms including delirium and EPS. This case will discuss the challenges of continuity of care in delirious, psychotic, or otherwise confused patients, including contributions from the COVID-19 pandemic. A medication card or other improvements in medication databases that may reduce delays in treatment are discussed.

Occurrence of acute cholinergic syndrome in an infant due to donepezil ingestion.

Donepezil and acetyl cholinesterase inhibitors are the most commonly prescribed medications for the treatment of Alzheimer's disease. We describe a 2-year-old infant who was referred to the emergency department after developing cholinergic syndrome 6 hours after ingesting 10 mg of his grandmother's donepezil tablets and was finally discharged in stable condition.

Alleviation of Abdominal Pain due to Irinotecan-Induced Cholinergic Syndrome Using Loperamide: A Case Report.

Irinotecan hydrochloride (irinotecan) is a chemotherapeutic agent used in the treatment of solid tumors. In addition to severe neutropenia and delayed diarrhea, irinotecan causes cholinergic syndrome, characterized by abdominal pain and acute diarrhea. The latter symptoms are frequently observed during and after irinotecan treatment. Here, we have discussed the case of a patient who completely recovered from abdominal pain following the administration of loperamide hydrochloride (loperamide) at a dose of 2 mg, before infusing irinotecan. In contrast, anticholinergic drugs were not as effective in alleviating symptoms. A 28-year-old man with stage IV rectal cancer with peritoneal metastasis was prescribed with fluorouracil, irinotecan, and levofolinate calcium (FOLFIRI), in addition to cetuximab. Anticholinergic drugs, such as scopolamine butylbromide (scopolamine) or atropine sulfate (atropine), were administered to treat abdominal pain that was considered as irinotecan-induced cholinergic syndrome, but monotherapy was not effective. Thereafter, oral loperamide (2 mg) with atropine (0.25 mg) was prescribed before irinotecan infusion. Consequently, the patient did not experience any abdominal pain during and after irinotecan treatment. Loperamide is an opioid receptor agonist and decreases the activity of the myenteric plexus of the intestinal wall. It also inhibits the release of both acetylcholine and prostaglandins, resulting in decreased inhibition of peristaltic movement. We assumed that its mechanism solely or in combination contributed to symptom relief. We hypothesized that the synergistic anticholinergic interaction between loperamide and atropine resulted in marked suppression of irinotecan-induced cholinergic syndrome compared to loperamide alone. Thus, loperamide may improve abdominal pain attributed to irinotecan-induced cholinergic syndrome.

Prophylactic effect of scopolamine butylbromide, a competitive antagonist of muscarinic acetylcholine receptor, on irinotecan-related cholinergic syndrome.

BACKGROUND/AIM: Cholinergic syndrome frequently occurs within the first 24 h after irinotecan injection. We evaluated the prophylactic effect of scopolamine butylbromide on irinotecan-related cholinergic syndrome. PATIENTS AND METHODS: Fifty-nine patients who received irinotecan-based regimens at our outpatient chemotherapy clinic between April 2013 and May 2014 were enrolled. Patients who developed irinotecan-related cholinergic syndrome were prophylactically administered scopolamine butylbromide at the next scheduled treatment. Risk factors for irinotecan-related cholinergic syndrome were determined using logistic regression analysis. RESULTS: Irinotecan-related cholinergic syndrome occurred in 50.8% of patients. Scopolamine butylbromide administration significantly reduced the incidence to 3.4% (P < 0.01). The irinotecan dose (≥ 150 mg/m2) was the only risk factor associated with irinotecan-related cholinergic syndrome. The incidence of cholinergic syndrome in patients with this risk factor was 75%. CONCLUSION: Scopolamine butylbromide was effective in preventing irinotecan-related cholinergic syndrome. It is recommended for patients receiving ≥ 150 mg/m2 irinotecan who may develop cholinergic syndrome at high frequency.

Coadministration of cytotoxic chemotherapeutic agents with irinotecan is a risk factor for irinotecan-induced cholinergic syndrome in Japanese patients with cancer.

BACKGROUND: Cholinergic syndrome is an acute adverse event frequently observed in patients administered irinotecan, and can sometimes negatively affect their quality of life. In some manifestations of the syndrome such as bradycardia, careful monitoring of patients is advised. In this study, we retrospectively investigated the risk factors associated with irinotecan-induced cholinergic syndrome in Japanese patients with cancer. METHODS: Patients who received irinotecan-based chemotherapy between April 2014 and June 2018 were examined. Patient backgrounds and clinical data during the first cycle of an irinotecan-containing regimen, including cholinergic syndrome manifestation within 24 h after the start of treatment, were collected from medical records. Univariate and multivariate analyses were performed to assess the risk of irinotecan-induced cholinergic syndrome. RESULTS: Among 179 patients administered an irinotecan-containing regimen, 51 experienced cholinergic syndrome after the initiation of treatment. The most common symptom was sweating followed by diarrhea, abdominal pain, lacrimation, and nasal discharge. 42 patients developed symptoms of cholinergic syndrome during their first treatment with irinotecan. Multivariate analyses revealed that the incidences of cholinergic syndrome in patients administered 2 or 3 chemotherapeutic agents; i.e., irinotecan plus 1 or 2 other cytotoxic anticancer drug(s), were significantly higher than that in patients administered irinotecan alone [odds ratio (OR) 4.35, 95% confidence interval (CI) 1.5-12, p = 0.0053 and OR 4.50, 95% CI 1.5-14, p = 0.0093, respectively]. The addition of a molecularly targeted drug did not affect the incidence of cholinergic syndrome. CONCLUSION: The incidence rate of irinotecan-induced cholinergic syndrome increased concomitantly with the addition of cytotoxic chemotherapeutic agents administered.

Predictive factors for the development of irinotecan-related cholinergic syndrome using ordered logistic regression analysis.

Cholinergic syndrome is an acute adverse reaction associated with irinotecan. Development of cholinergic syndrome can be ameliorated or prevented by administering various anticholinergics, including atropine sulfate or scopolamine butylbromide. Although many of the side effects are transient and non-life-threatening, their onset is painful and can lower a patient's quality of life (QoL). This retrospective study was performed to identify predictive factors of the development of irinotecan-related cholinergic syndrome in order to develop future strategies for improving the QoL of patients undergoing chemotherapy. We enrolled 150 cancer patients who underwent chemotherapy, which included irinotecan, in our outpatient chemotherapy center between October 2014 and January 2017. For regression analysis, variables related to the development of irinotecan-related cholinergic syndrome were extracted from the patient's clinical records. The degree of cholinergic syndrome was classified as follows: grade 0 = not developed; grade 1 = developed but did not require anticholinergic drugs; and grade 2 = developed and required anticholinergic drugs or stopping the chemotherapy due to cholinergic syndrome. Multivariate ordered logistic regression analysis was performed to identify predictive factors for the development of irinotecan-related cholinergic syndrome. Threshold measurements were determined using a receiver operating characteristic analysis (ROC) curve. Significant factors identified for the development of cholinergic syndrome included female sex [odds ratio (OR) 2.183, 95% confidence interval (CI) 1.010-4.717; P = 0.0471] and irinotecan dose (OR 1.014, 95% Cl 1.007-1.021; P = 0.0001). ROC curve analysis of the group likely to develop cholinergic syndrome indicated that the threshold for the irinotecan dose was 175 mg or above (area under the curve = 0.69). In conclusion, female sex and irinotecan dose were identified as significant predictors of the development of cholinergic syndrome.

Delayed Polyneuropathy Induced by Organophosphate Poisoning.

An 89-year-old man attempted suicide by ingesting a pesticide (trichlorfon). After surviving the initial critical period in the intensive care unit, he developed rapidly progressive distal weakness and sensory disturbance. Electrophysiological examinations revealed sensory motor axonal polyneuropathy. Delayed polyneuropathy is a rare manifestation of organophosphate poisoning. Nerve conduction studies play an important role in the diagnosis of this rare clinical condition.

Acute cholinergic syndrome in a patient with mild Alzheimer's type dementia who had applied a large number of rivastigmine transdermal patches on her body.

CASE PRESENTATION: A 91-year-old woman was transferred to our Emergency Medical Center and Poison Center with somnolence, hypertension (186/61 mm Hg), and repeated vomiting. Three hours later, 10 transdermal patches, each containing 18 mg of rivastigmine (9.5 mg/24 h), were found on her lower back and both thighs, when miosis, facial and trunk sweating, enhanced bowel sound, hypertension, and sinus tachycardia were noted. She was diagnosed with acute cholinergic syndrome due to rivastigmine poisoning. Her hypertension and sinus tachycardia peaked 8 and 5 h after all the patches were removed, respectively. Her symptoms subsided spontaneously after 17 h. DISCUSSION: In the present case, our patient was presented with acute cholinergic syndrome due to carbamate intoxication after massive transdermal exposure to rivastigmine. Toxicological analysis revealed a remarkably high estimated serum rivastigmine concentration (150.6 ng/ml) and notably low serum butyrylcholinesterase activity (35 IU/l) on admission, with a markedly prolonged calculated elimination half-life of 6.5 h. CONCLUSIONS: Emergency physicians should consider acetylcholinesterase inhibitor exposure (e.g., rivastigmine) when patients are present with acute cholinergic syndrome.

Transient cardiac effects in a child with acute cholinergic syndrome due to rivastigmine poisoning.

BACKGROUND: We report a case of rivastigmine poisoning resulting in a full cholinergic syndrome with nicotinic, muscarinic, and central effects requiring supportive or intensive care in a pediatric patient. CASE REPORT: A 3-year-old girl was admitted to the Emergency Department suspected of having ingested one or two pills of rivastigmine. The child was hyporeactive, with symptoms of altered mental status, sialorrhea, sweating, and diarrhea. Subsequently, she started showing signs of respiratory failure, severe tracheobronchial involvement, and gastric and abdominal distension. An electrocardiogram recorded frequent monomorphic ventricular ectopic beats with bigeminy and trigeminy. Long-term follow-up showed a transient dysrhythmia. CONCLUSION: Poisoning with rivastigmine can be a life-threatening condition. Timely identification and appropriate management of the toxic effects of this drug are essential and often life-saving. This is particularly true in cases of cholinergic syndrome subsequent to drug poisoning. Patients with cholinergic syndrome should also be assessed for possible cardiac complications such as dysrhythmias. The main factors predisposing to the development of such complications are autonomic disorder, hypoxemia, acidosis, and electrolyte imbalance.