Improving access to antidotes and antivenoms, Thailand.

PROBLEM: Historically in Thailand, access to poison antidotes was limited and antivenom stock management was inefficient. APPROACH: In 2010, the country established a national antidote programme, which created national and subnational antidote stocks, managed their distribution and trained health-care providers on clinical management and antidote use. In 2013, the programme incorporated antivenoms to improve stock management and avoid wastage due to stock expiry. LOCAL SETTING: Before the programme, health-care providers consulted poison centres on clinical management of poisoning and some antidotes were not available. Individual hospitals stocked antivenoms, which often expired before use. RELEVANT CHANGES: Today, the National Health Security Office finances and manages the centralized procurement of antidotes and antivenoms and all Thai patients have a right to antidotes regardless of health insurance. National and subnational stock levels are determined based on demand, treatment urgency and cost. A web-based system, which incorporates geographical information, was introduced for requesting antidotes and antivenoms. Poison centres provide training, 24-hour consultation services and outcome monitoring. Antidotes and antivenoms are now readily available and used correctly and clinical management has improved. Moreover, better stock and distribution control has helped avoid antivenom wastage and reduced antivenom costs, from US$ 2.23 million United States dollars (US$) to US$ 1.2 million. LESSONS LEARNT: The programme's success depended on strong and sustained policy support, adequate funding, improved operational capacity, training for health-care professionals and the provision of 24-hour online consultation services. A web-based centralized procurement and distribution ensured these essential medicines were available, minimized costs, reduced waste and saved lives.

FIRST IDENTIFICATION OF HEMOGLOBIN LANSINGRAMATHIBODI [α87(F8)His → Gln; CAC>CAG (HBA1: c.264C>G)] IN A THAI FAMILY WITH SPURIOUS HYPOXEMIA.

We report, for the first time, hemoglobin (Hb) Lansing-Ramathibodi [α87(F8)His → Gln; CAC>CAG (HBA1: c.264C>G)] in four members of a Thai family presented with low measured oxygen saturation by pulse oximetry (SpO2), with discrepancy between low SpO2 and normal calculated oxygen saturation by arterial blood gas analysis, and no cyanosis or methemoglobinemia. The causative mutation is located in HBA1 whereas in previous reports of Hb Lansing the mutation is on HBA2, including that in a Japanese individual. The index and a male sibling also co-inherited Hb Pakse, a non-deletional α-thalassemia 2, resulting in mild reticulocytosis. Correct Hb identification is crucial for genetic counselling and, thereby, avoiding unnecessary investigation and treatment for spurious hypoxemia.

OCCUPATIONAL CARBAMATE POISONING IN THAILAND.

Carbamate insecticide is a leading cause of poisoning in Thailand. The objective of this study was to characterize the clinical manifestations and modes of occupational exposure in carbamate poisoning cases. We retrospectively studied all the cases of carbamate poisoning due to occupational exposure recorded in the Ramathibodi Poison Center Toxic Exposure Surveillance system during 2005 to 2010. Demographic data, clinical manifestations and severity were analyzed statistically. During the study period, 3,183 cases were identified, of which 170 (5.3%) were deemed to be due to occupational exposure. Ninety-six cases (56.5%) and 35 cases (20.6%) were poisoned by carbofuran and methomyl, respectively. Carbofuran is sold as a 3% grain and applied by sowing; methomyl is sold as a liquid and is applied by spraying. The majority of poisoned patients did not wear personal protective equipment (PPE) while applying the carbamates. The clinical manifestations of occupational carbofuran poisoning recorded were nausea and vomiting (82.3%), headaches (56.3%) and miosis (19.8%). The clinical manifestations of methomyl poisoning were nausea and vomiting (74.3%), headaches (57.1%) and palpitations (11.4%). Most patients in both groups had mild symptoms. Only one case in each group required endotracheal intubation and mechanical ventilation support. There were no deaths and the lengths of hospitalization ranged from 2 hours to 2 days. Occupational carbamate poisoning cases in our series were mostly mild and the patients recovered quickly. There were only rare cases of serious symptoms. Lack of knowledge and inadequate PPE were the major factors contributing to occupational poisoning. Educating agricultural workers about correct precautions and pesticide use could minimize this type of poisoning.

PLANT POISONING IN THAILAND: A 10-YEAR ANALYSIS FROM RAMATHIBODI POISON CENTER.

Plant poisoning is not uncommon in Thailand. The objective of this study was to determine the incidence, type, clinical manifestations, severity and outcomes of plant poisoned patients in Thailand over a 10-year period. We retrospectively reviewed data from the Ramathibodi Poison Center Toxic Exposure Surveillance System for 2001-2010. A total of 2,901 poisonous plant exposure cases were identified, comprising 3.1% of the 92,392 poison cases recorded during the study period. This was the fifth most common type of poisoning recorded. Children aged < 13 years comprised the largest percent (69.8%) of the cases. The major type of exposure was unintentional ingestion. Ninety-nine types of poisonous plants were recorded as the causative agents among 99.1%of the cases. Gastrointestinal symptoms were reported in 72.0% of cases with Jatropha curcas (physic nut) comprising 54.1% of these. Most patients had only minor signs and symptoms. The mortality rate among the total plant poisoning cases was 0.9%, with 26 deaths. Thirteen deaths occurred in children aged < 13 years. The greatest number of fatalities were due to ingestion of Manihot esculenta (cassava), primarily due to multi-system organ failure. Children aged < 13 years are at the greatest risk for plant poisoning in Thailand; mostly unintentional. Most cases were minor and the mortality rate was low. Jatropha curcas was the most common cause of poisoning and Manihot esculenta was the most common cause of death. Public education is important to minimize these poisonings.

Clinical features of seven patients poisoned with a tolfenpyrad-based insecticide in Thailand.

INTRODUCTION: Tolfenpyrad, a novel insecticide originating from Japan and first approved in 2002, has been marketed in numerous countries. Data on tolfenpyrad exposure in humans are limited. This study aimed to characterize the clinical features and outcomes of acute poisoning from tolfenpyrad-based insecticides in Thailand. METHODS: This retrospective study analyzed cases of tolfenpyrad exposure reported to the Ramathibodi Poison Center from 2012 to 2022. RESULTS: A total of seven patients were identified, with the majority being male (n = 5). Deliberate tolfenpyrad exposure accounted for three cases. The median age was 33 (range 1-46) years. Severe systemic effects were evident at presentation in the four patients ingesting tolfenpyrad. These included altered mental status (n = 4), mydriasis (n = 2), cardiac arrest (n = 1), hypotension (n = 4), bradycardia (n = 2), and high anion gap metabolic acidosis (n = 4). The median time from exposure to hospital presentation was 30 (range 15-60) minutes. All four patients ingesting tolfenpyrad died, whereas the three patients exposed via inhalation and dermally developed only mild clinical effects, and all were discharged following supportive care. DISCUSSION: We observed many of the clinical features reported previously, including vomiting, mydriasis, altered mental status, metabolic acidosis, and hypotension. We also noted a combination of bradycardia and hypotension while not observing respiratory depression. CONCLUSIONS: Tolfenpyrad insecticide poisoning has been reported infrequently. Rapid systemic toxicity can follow ingestion, resulting in a high mortality. Larger-scale studies are essential to identify predictors of severity and determine the optimal treatment for tolfenpyrad-poisoned patients.

Kratom abuse in Ramathibodi Poison Center, Thailand: a five-year experience.

Kratom (Mitragyna speciosa Korth), a native tree in Southeast Asia, is misused as an abuse drug and becomes legally widespread to several countries. Currently, it is available through the online market or by some shops. The clinical manifestations of Kratom's effects are not well-defined and the clinical studies are limited. This study was designed to identify the characteristics of Kratom poisoning and withdrawal cases from Kratom exposure cases in Ramathibodi Poison Center (RPC), Thailand, during a five-year period. We used a retrospective review of Kratom exposure cases from the RPC toxic surveillance system. A total of 52 Kratom exposure cases were identified. The trend of case consultations has been increasing. There were Kratom poisoning cases (76.9%) and withdrawal cases (23.1%). Common presenting symptoms in the poisoning group were palpitation (22.5%), followed by seizure (17.5%). For the withdrawal group, the common presenting symptoms were myalgia (33.3%), insomnia (16.67%), fatigue (16.67%), and chest discomfort (16.67%). There was a baby with withdrawal symptoms who was delivered from a chronic Kratom-abusing mother, suggesting possible exposure via the transplacental route. There were no deaths in either group. Kratom abuse can cause either poisoning or withdrawal. Most cases in both groups had good prognostic outcome.

A Retrospective Cohort Study of Cobra Envenomation: Clinical Characteristics, Treatments, and Outcomes.

This study investigated the clinical characteristics, treatments, and outcomes of envenomation involving cobra species in Thailand (Naja kaouthia, Naja siamensis, and Naja sumatrana). Data of patients who had been bitten by a cobra or inoculated via the eyes/skin in 2018-2021 were obtained from the Ramathibodi Poison Center. There were 1045 patients admitted during the 4-year study period (bite, n = 539; ocular/dermal inoculation, n = 506). Almost all patients with ocular/dermal inoculation had eye involvement and ocular injuries, but none had neurological effects. Most of the patients bitten by a cobra had local effects (69.0%) and neurological signs and symptoms (55.7%). The median interval between the bite and the onset of neurological symptoms was 1 h (range, 10 min to 24 h). Accordingly, patients should be observed closely in hospitals for at least 24 h after a bite. Intubation with ventilator support was required in 45.5% of patients and for a median duration of 1.1 days. Antivenom was administered in 63.5% of cases. There were nine deaths, most of which resulted from severe infection. Neurological effects and intubation were significantly more common after a monocled cobra bite than after a spitting cobra bite. The administration of antivenom with good supportive care, including the appropriate management of complications, especially wound infection, might decrease fatality.

A 10-Year Retrospective Analysis of Medication Errors among Adult Patients: Characteristics and Outcomes.

Medication errors (MEs) are a global health problem. We conducted this study to clarify the clinical characteristics, outcomes, and factors associated with MEs that caused harm to adult patients (>15 years of age) who were managed in hospitals or healthcare facilities. We performed a 10-year retrospective study (2011-2020) by analyzing data from the Ramathibodi Poison Center (RPC) database (RPC Toxic Exposure Surveillance System). There were a total of 112 patients included in this study. Most were women (59.8%) and had underlying diseases (53.6%). The mean patient age was 50.5 years. Most MEs occurred during the afternoon shift (51.8%) and in the outpatient department (65.2%). The most common type of ME was a dose error (40.2%). Local anesthetic was the most common class of ME-related drug. Five patients died due to MEs. We analyzed the factors associated with MEs that caused patient harm, including death (categories E-I). The presence of underlying diseases was the single factor that was statistically significantly different between groups. Clinical characteristics showed no significant difference between patients aged 15-65 years and those aged >65 years. In conclusion, our findings emphasized that MEs can cause harm and even death in some adult patients. Local anesthetics were the most commonly involved in MEs. Having an underlying disease might contribute to severe consequences from MEs. Preventive measures and safety systems must be highlighted and applied to prevent or minimize the occurrence of MEs.

Poisoning from Ingestion of Fungus-Infected Cicada Nymphs: Characteristics and Clinical Outcomes of Patients in Thailand.

The current data regarding poisoning associated with ingestion of fungus-infected cicada nymphs are limited. We performed a retrospective cohort study of patients who ingested fungus-infected cicada nymphs and were referred to the Ramathibodi Poison Center for consultation from June 2010 to June 2022. Thirty-nine patients were included for analysis. Most were men (53.8%). Mean age was 40.2 ± 15.0 years. All nymphs were ingested as a health/food supplement. Thirty-one patients (79.5%) reported gastrointestinal symptoms. Median time from ingestion to symptom onset was 5 h. Twenty-nine patients (74.4%) reported neurological symptoms, including tremor, myoclonus, muscle rigidity, nystagmus/ocular clonus, drowsiness, dysarthria, seizure, and confusion. Some complained of dizziness, urinary retention, and jaw stiffness. Most patients (94.9%) were admitted to the hospital. Median hospital stay was 3 days. Ibotenic acid was detected in the blood and urine samples of one patient. All received supportive care. Four patients developed infectious complications. No deaths occurred. Consuming fungus-infected cicada nymphs may cause poisoning in humans. Gastrointestinal and neurological symptoms were common. Ibotenic acid might be the underlying cause. The main treatment is supportive care and appropriate management of complications. Education of the general public is advocated to prevent the incidence of this type of poisoning.

Clinical characteristics, treatment and outcomes of acute propanil poisoning in a 7-year retrospective cohort study.

The present study was a 7-year retrospective cohort study (2012-2018) of patients treated for acute propanil poisoning by ingestion, using data from Ramathibodi Poison Center, Thailand. The aim of this study was to describe the clinical characteristics, treatment, outcomes and factors associated with moderate to severe outcomes and death following acute exposure to propanil. The effect of administering multiple-dose activated charcoal (MDAC) on clinical outcomes was also evaluated. A total of 275 cases were included. The results show that two thirds of patients were male and mean age was 40 years. Patients ingested either propanil or a mixture of propanil and other herbicides. The majority (98%) of exposures was intentional. Most patients (65.5%) presented with gastrointestinal symptoms. Methemoglobinemia and hemolysis were observed in 108 patients (39.3%) and 25 patients (9.1%), respectively. Median time to onset of methemoglobinemia and hemolysis after propanil ingestion was 5.5 and 48 h, respectively. One hundred and forty-one patients (51.3%) were treated with MDAC, and some patients received methylene blue (21.5%), intubation (18.5%), or blood transfusions (8%). All patients were admitted to hospitals. The median length of hospital stay of patients who survived was 3 days. Multivariate analysis indicated that neurological symptoms at presentation, methemoglobinemia and acute kidney injury during admission, were associated with moderate to severe outcomes. Factors associated with mortality were older age, larger amount of ingestion, neurological symptoms at presentation and hypotension during admission. The overall mortality rate was 6.2%. The mortality rate was 3.6% in patients that received MDAC and 9% in patients that did not, although the difference was not statistically significant. Subgroup analysis of patients who developed methemoglobinemia or both methemoglobinemia and hemolysis found a statistically significant lower mortality rate in patients that received MDAC. In conclusion, methemoglobinemia and hemolysis contribute to poor outcomes in acute propanil poisoning. Age, amount of ingestion, neurological symptoms at presentation and hypotension during admission could prognosticate deaths, and patients with these factors should be closely observed and aggressively managed.

Early Adverse Reactions to Snake Antivenom: Poison Center Data Analysis.

Antivenom is an essential treatment for snake envenomation; however, early adverse reactions (EARs) are major limitations to its use. We performed a retrospective cross-sectional study using Ramathibodi Poison Center data (January 2016 to December 2017) to clarify the incidence and severity of EARs following different F(ab')2 antivenoms. Among 1006 envenomed patients, 684 (68%) received antivenom therapy with a total of 1157 doses, mostly green pit viper antivenom. The overall EAR incidence and rate were 22. 5% (154/684) and 15% (173/1157), respectively. The EAR rate following each type of antivenom was >10%, except for Russell's viper antivenom (2.9%); the severe reaction rate was 2.6% (30/1157). Malayan pit viper bites caused a high incidence of EARs (37.8%) and the highest EAR rate (22.3%). Fifty-two cases developed anaphylaxis. All EARs occurred within 2 h after treatment initiation. No deaths were attributed to EARs. The duration of administration was significantly different between doses of antivenom that induced EARs and those that did not. In conclusion, all types and every dose of antivenom should be infused for 30−60 min. Preparation of resuscitation equipment and continuous clinical observation are crucial for at least 2 h after administration, and prompt treatment should be provided when EARs occur.

Characteristics and Consequences of Medication Errors in Pediatric Patients Reported to Ramathibodi Poison Center: A 10-Year Retrospective Study.

Purpose: This study was performed to evaluate the clinical characteristics of, consequences of, and factors associated with medication errors (MEs) that cause harm to pediatric patients (<15 years of age) treated in the hospital setting. Patients and Methods: We performed a 10-year retrospective study (January 2011-December 2020) by analyzing data from the Ramathibodi Poison Center. MEs were classified into categories A to I according to the severity of the outcome. Results: In total, 121 patients were included in the study. Most (51.24%) patients were male. Their median age was 1 year (range, 1 hour-14 years). Infants, newborns, and toddlers were the three most common age groups in which MEs were reported. Most MEs occurred during the afternoon shift [n = 60 (49.59%)] and in the inpatient department (66.12%). The most common type of MEs was a dose error (64.46%). Antibiotics, sedative agents, and bronchodilators were the three most common classes of ME drugs. Four patients died. Three deaths occurred because of a dose error. One patient was a 1-year-old girl who received an iatrogenic intravenous phenytoin overdose of 10 times the normal dose, resulting in a phenytoin level of 72.4 mcg/mL. She died 22 hours after the ME occurred. The work shift was the only factor that significantly differed between patients with category C and D MEs and those with category E to I MEs. Conclusion: Small children were at highest risk for MEs. MEs induced harm and deaths in some patients. A preventive and safety system, including appropriate shift work administration, should be emphasized and implemented to prevent and/or decrease the occurrence of MEs.

Clinical effects and factors associated with adverse clinical outcomes of hymenopteran stings treated in a Thai Poison Centre: a retrospective cross-sectional study.

OBJECTIVE: To describe clinical effects and outcomes of hymenopteran stings and to explore the non-laboratory factors associated with adverse clinical outcomes, a composite outcome including death, respiratory failure requiring intubation, acute kidney injury (AKI) requiring dialysis and hypotension requiring vasopressor use. METHODS: A retrospective cross-sectional study was performed at the Ramathibodi Poison Center, a poison centre of a tertiary care hospital in Thailand. All cases of hymenopteran sting consultations from January 2015 to June 2019 were consecutively enrolled, and charts were reviewed. Demographics, initial clinical characteristics and outcomes were collected. Factors associated with adverse clinical outcome were explored. RESULTS: One hundred and fourteen hymenopteran stings cases (wasp 48%, bee 33%, hornet 14% and carpenter bee 8.8%) were included (median age, 36.5 years (interquartile range 9-55); male 63%). The prevalence of adverse clinical outcomes was 12.3% (95%CI 6.88-12.8). At initial presentation, 100% of cases had local skin reactions, 11.4% were clinical anaphylaxis, and 8% had red urine. Adverse clinical outcomes included death (n = 10), respiratory failure requiring intubation (n = 9), AKI requiring dialysis (n = 6) and hypotension requiring vasopressor use (n = 2). None of the patients with carpenter bee or hornet stings developed adverse clinical outcomes. In univariable analysis, urticaria, wheezing, red urine, wasp sting and sting number > 10 were significantly associated with adverse clinical outcomes. In multivariable analysis, red urine (adjusted OR 11.1 (95% CI 1.57-216)), wheezing (adjusted OR 16.7 (95% CI 1.43-402)) and a number of stings > 10 (adjusted OR 21.5 (95% CI2.13-2557)) were significant. CONCLUSIONS: Adverse clinical outcomes in hymenopteran stings were not uncommon among cases inquiring to a national Thai poison centre. At initial presentation, red urine, wheezing and a number stings >10 were significantly associated with adverse clinical outcomes. Larger epidemiologic studies are required to confirm these associations.

Clinical response and safety of malathion shampoo for treatment of head lice in a primary school.

OBJECTIVE: Help eradicate or at least alleviating head lice in a primary school with malathion shampoo and to study clinical response and safety of malathion shampoo. MATERIAL AND METHOD: All students were examined by using a fine-toothed lice comb to help detect live lice. Direct visual examination and the collection of nits for microscopic examination were performed to differentiate viable nits from empty nits. Diagnosis of head lice was made by the presence of lice. All students that had lice and/or nits were treated with malathion shampoo. Malathion shampoo was also provided for all family members. Pediculocidal efficacy was by the presence or absence of live lice. Blood for red blood cell cholinesterase activity was drawn in 32 volunteers before treatment and after the second treatment. RESULTS: At the first visit, 629 students were examined and 48 students had live head lice. The infestation rate was 13% in girls and 1.3% in boys. The cure rate was 93% after the first treatment. The reported side effects were nausea, a burning sensation, and irritation that was found in five (4%), 10 (7%) and three (2%) students respectively. The mean of RBC cholinesterase activity before and after two applications showed significant changes (p = 0.03). It was -7.5 +/- 4.1% reduction from the initial, but all were in the normal range. There was no report of clinical manifestation of malathion toxicity. CONCLUSION: Malathion shampoo is safe and effective in the treatment of head lice. There is significant skin absorption so a scalp examination for head lice should be done before subsequent application to avoid unnecessary exposure.

Poisoning of Butanol-Containing Products: Clinical Characteristics and Outcomes.

BACKGROUND: Butanol (butyl alcohol) is a chemical which occurs naturally in some foods and is used in the manufacture of other chemicals. Current data on butanol poisoning in humans are limited. OBJECTIVE: This study describes clinical characteristics and outcomes of patients exposed to products containing butanol. METHODS: We performed a 5-year retrospective cross-sectional study by analyzing data from the Ramathibodi Poison Center Toxic Exposure Surveillance System for 2013-2017. RESULTS: There were 163 patients included in the study. All products containing butanol reported were agricultural adjuvant products. Most (67.5%) patients were males and had ingested butanol accidentally (75.5%). The median age was 42 years. Almost all patients had oral exposure to butanol. At presentation, most of our patients had normal vital signs and were conscious. Clinical presentations mostly included gastrointestinal symptoms (65%) and local irritation (28.8%). Fifty-four patients (33.1%) had no obvious clinical effects at presentation. Most patients had normal laboratory tests at presentation, although eight developed systemic effects including high anion gap metabolic acidosis (n=8), acute kidney injury (AKI; n=5), depression of consciousness (n=5), and hypotension (n=3). Of these eight patients, two with intentional ingestion developed altered consciousness, hypotension, AKI, severe metabolic acidosis, and eventually died. One of these died within 1 day after ingestion, while the other died later through complications during admission. Therefore, the mortality rate was 1.23%. Sixty-six patients (40.5%) were admitted to hospitals, with a median length of stay of 1 day. Most patients received only supportive treatment and fully recovered. CONCLUSION: Agricultural adjuvant products containing butanol or butanol itself caused only mild effects in most patients, but systemic effects occurred in some. The mortality from this poisoning was very low, and both fatalities were from intentional ingestion. Supportive care and proper management of complications should be the main treatment for this form of poisoning.

Development of a Physiologically Based Pharmacokinetic Model of Mitragynine, Psychoactive Alkaloid in Kratom (Mitragyna Speciosa Korth.), In Rats and Humans.

Mitragynine is a major psychoactive alkaloid in leaves of kratom (Mitragyna speciosa Korth.). To understand its disposition in organs, this study aimed to develop a physiologically based pharmacokinetic (PBPK) model that predicts mitragynine concentrations in plasma and organ of interests in rats and humans. The PBPK model consisted of six organ compartments (i.e. lung, brain, liver, fat, slowly perfused tissues, and rapidly perfused tissue). From systematic searching, three pharmacokinetic studies of mitragynine (two studies in rats and 1 study in humans) were retrieved from the literature. Berkeley Madonna Software (version 8.3.18) was used for model development and model simulation. The developed PBPK model consisted of biologically relevant features following involvement of (i) breast cancer-resistant protein (BCRP) in brain, (ii) a hepatic cytochrome P450 3A4 (CYP3A4)-mediated metabolism in the liver, and (iii) a diffusion-limited transport in fat. The simulations adequately describe simulated and observed data in the two species with different dosing regimens. PBPK models of mitragynine in rats and humans were successfully developed. The models may be used to guide optimal mitragynine dosing regimens.

Poisoning of glutaraldehyde-containing products: clinical characteristics and outcomes.

OBJECTIVE: This study describes the clinical characteristics, outcomes, and factors at presentation associated with death of cases poisoned by glutaraldehyde (GA)-containing products. METHODS: We performed a 5-year retrospective cohort study (July 2013-June 2018) using data from the Ramathibodi Poison Center. RESULTS: There were 244 cases included in this study. Most were men with a median age of 37 years. The GA-containing products were mainly used as farm disinfectants (99.2%), with a median concentration of 15%. Most products (76.2%) contained co-formulants such as cationic detergents and formaldehyde.Most circumstances were accidental (56.9%). The others were suicide attempts by ingestion, except one patient who intentionally injected GA subcutaneously. The most common route of exposure was ingestion (95.0%). Local symptoms in areas of exposure were common. Ingestion resulted in more severe local effects than other routes, and corrosive effects occurred in 23 cases (9.4%). Systemic signs and symptoms occurred in 149 patients (61.1%). Systemic effects included abnormal vital signs, desaturation, altered mental status, hypo/hypernatremia, hypokalemia, low bicarbonate/metabolic acidosis, acute kidney injury (AKI), hepatitis, and rhabdomyolysis. Systemic effects mostly resulted from ingestion. Most patients had mild severity, received only supportive treatment, and fully recovered. The median length of hospital stay was 2 days. The one case of subcutaneous injection developed both local and systemic effects but survived. The mortality rate was 3.7%. Multivariate analysis indicated that either neurological symptoms or AKI at presentation were associated with death. CONCLUSIONS: In our study, patients were exposed to GA-containing products that were mainly used as farm disinfectants and were generally co-formulated with other substances. Poisoning with these products commonly resulted in mild local irritative symptoms. However, some cases developed corrosive symptoms, systemic effects, or even died. As neurological symptoms or AKI could prognosticate deaths; physicians should look for these factors in patients with GA exposure at presentation for close monitoring and aggressive treatment.

Malayan Pit Viper Envenomation and Treatment in Thailand.

INTRODUCTION: The Malayan pit viper (MPV; Calloselasma rhodostoma) is a hematotoxic snake found in all regions of Thailand and many countries in Southeast Asia. Treatment of MPV envenomation varies among facilities due to their capabilities. MATERIALS AND METHODS: This study was a retrospective review of patients with MPV envenomation who were reported to the Ramathibodi Poison Center from 1 July 2016 to 30 June 2018. RESULTS: Of the 167 patients (median age, 40.5 years; range, 1.3-87.0 years) bitten by an MPV, the most common bite site was the foot (29.3%). Most patients reached the hospital within 1 hour of being bitten. One-hundred fifty-six patients (93.4%) had local effects from envenomation; 17 patients (10.2%) had severe local complications including necrotizing fasciitis (3.0%) and compartment syndrome (7.2%). Systemic effects such as hemorrhage and abnormal hemostasis occurred in 147 patients (88.0%). Additional effects included abnormal venous clotting time in 123 patients (73.7%), unclotted 20-minute whole blood clotting time in 57 patients (34.1%), low platelet counts (<50,000/µL) in 29 patients (17.4%), prolonged international normalized ratio (>1.2) in 51 patients (30.5%), and systemic bleeding in 14 patients (8.4%). The median onset of bleeding disorder was 6 hours. Monitoring for 24, 48, and 49 hours after bite enabled detection of systemic effects in 94.2%, 99.3%, and 100.0%, respectively. Three hundred fifteen courses of antivenin were administered to 144 patients (86.2%). All the patients who received antivenin recovered from bleeding disorder. Only 7.0% of antivenin doses were administered without Thai Red Cross indications. Allergic reactions from antivenin occurred in 34.7% of the 144 patients. One hundred thirty patients (77.8%) received antibiotics, and 32 patients (19.2%) required surgical management, including debridement and fasciotomy. CONCLUSION: MPV envenomation results in local and systemic effects. Most systemic effects were abnormal clotting test results. Most patients reported onset of bleeding disorder within 48 hours.

Effect of activated charcoal in reducing paracetamol absorption at a supra-therapeutic dose.

BACKGROUND: Activated charcoal (AC) is recommended for treatment of acute poisoning, thereby decreasing gastrointestinal tract absorption. AC from different sources may have different adsorptive capacity. The AC that is available in Thailand has not been proven yet for its efficacy The authors simulated paracetamol overdose model for the present study. OBJECTIVE: To assess the efficacy of AC that is available in Thailand in decreasing absorption of paracetamol at supratherapeutic dose. MATERIAL AND METHOD: This was a two-arm, prospective, crossover study. Washout period was 1 week Twelve healthy male volunteers participated. All volunteers were randomly assigned to either sequence of control-experiment (CE) or EC. The participants ingested 60 mg/Kg of paracetamol at Time=0. At Time = 0.25 hour, they ingested 50 g of AC as slurry with 250 ml of water when they were assigned as E, but drank 250 mL of water when were assigned as C. Blood samples were serially collected for determination of paracetamol concentration and calculating pharmacokinetic parameters, area under the time-concentration curve (AUC (0, infinity)). RESULTS: Means of the AUC (0, infinity) were 313.7 +/- 29.8 and 184.8 +/- 91.6 mg-h/ L in the control and experimental arm, respectively It was statistically different (p = 0.01). CONCLUSION: The tested AC was found to be able to reduce the absorption of the supratherapeutic dose of paracetamol.

Myotoxic Mushroom Poisoning in Thailand: Clinical Characteristics and Outcomes.

PURPOSE: To describe the clinical characteristics and outcomes of myotoxic mushroom poisoning in Thailand. PATIENTS AND METHODS: We performed a retrospective cohort study of cases of myotoxic mushroom poisoning from the Ramathibodi Poison Center Toxic Exposure Surveillance System during a 5-year period (2012-2016). RESULTS: Forty-one cases were included. Most (53.7%) were male with the average age of 49 years. In three cases, the mushrooms were identified as Russula species by an experienced mycologist. Common presenting symptoms were gastrointestinal (GI) symptoms and myalgia. The median onset of GI symptoms and symptoms suggesting rhabdomyolysis after consuming mushrooms was 2 hours (0.17-24 hours) and 24-48 hours (2-120 hours), respectively. Eight patients who ate the mushrooms together with other patients with rhabdomyolysis had GI symptoms but did not develop rhabdomyolysis. For patients with rhabdomyolysis, acute kidney injury (AKI) and hyperkalaemia occurred in 51.5% and 33.3% of cases, respectively. Median initial and maximum creatine phosphokinase (CPK) levels in patients with rhabdomyolysis were 31,145 and 47,861 U/L, respectively. Fifteen of 17 patients who were investigated for troponin levels had elevated troponin. Three patients had a low ejection fraction. Most patients (95.1%) were admitted to hospital, with a median stay of 5 days. The mortality rate was 26.8%. Treatments included intravenous fluid, urine alkalinization, haemodialysis and peritoneal dialysis. Among patients with rhabdomyolysis, AKI, hyperkalaemia during hospitalisation, maximum CPK level, maximum creatinine level and initial and maximum potassium levels were the factors found to be significantly different between patients who died and those who survived. CONCLUSION: Myotoxic mushroom poisoning had a high mortality rate. Most patients had early or delayed onset of clinical symptoms after mushroom ingestion. Some patients developed severe cardiovascular effects. Early detection, close monitoring (especially serum potassium, creatinine, CPK and cardiac effect) and good supportive care were the main treatment modalities.