Oral activated charcoal in the treatment of intoxications. Role of single and repeated doses

ICP-MS assessment of elemental impurities and metallic contaminants in activated charcoal products

Activated charcoal is an adsorbent material which is consumed as a dietary supplement (100 mg) and as non-specific antidote treatment in acute poisoning at 0.5-1 g kg-1 body weight in infants and 50 g in adults. The ingestion of large quantities of it has aroused our interest in the presence of metals impurities. Therefore, the present study aimed to assess trace elements in activated charcoal products. Multielement analysis were performed using Inductively Coupled Plasma-Mass Spectrometry after digestion. Estimated daily Intake was calculated and compared to references doses for each element. Varying trace elements have been found: chromium (0.3383 ± 0.089 µg g-1), cadmium (0.5991 ± 0.2967 µg g-1), aluminum (0.7033 ± 0.1215 µg g-1), nickel (0.0111 ± 0.003 µg g-1), lead (0.0052 ± 0.0021 µg g-1), zinc (0.0414 ± 0.0076 µg g-1), and manganese (0.0036 ± 0.0006 µg g-1). when 50 g of activated charcoal is consumed by a 70 kg adult, aluminum estimated daily intake is 0.0005 mg/kg bw/day which exceeds the reference dose (0.0004 mg/kg bw/day). In the infants, consumption of 15 g of contaminated activated charcoal exposes to chromium, cadmium and aluminum as their estimated daily intake (0.00034; 0.0006; 0.0007 mg/kg bw/day respectively) exceed their reference doses (0.0003; 0.0005; 0.0004 mg/kg bw/day respectively). These trace elements are not without risk to consumers health. Activated charcoal products could be contaminated with elemental impurities. Pharmaceutical industries should be vigilant to raw materials (plants and wood) used in the preparation, these materials should come from unpolluted areas to avoid contaminations.

Recent advances in Ti-based MOFs in biomedical applications

Currently, metal-organic frameworks (MOFs), basically inorganic-organic hybrid materials, have gained tremendous attention due to their vast applications. MOFs have shown enormous applications in almost every research field. However, the area of designing MOF materials for their biological applications is still an emerging field that needs attention. Titanium-based metal-organic framework (Ti-MOF) materials are used in many research areas due to their structural advantages, such as small particle size and large effective surface area. On the other hand, they have also shown unique advantages such as good biocompatibility, excellent catalytic oxidation and photocatalytic properties and ease of functionalization. This study reviews the recent research progress on Ti-MOFs in therapeutic areas such as antibacterial, oncology, anti-inflammation, and bone injury, which will provide new directions for further research in this biomedical field. Therefore, this article will help scientists working in the particular field to enhance their understanding of Ti-based MOFs for functional biomedical applications.

Compound Identification from Bromelia karatas Fruit Juice Using Gas Chromatography–Mass Spectrometry and Evaluation of the Bactericidal Activity of the Extract

Fruits of species of the genus Bromelia contain compounds with health benefits and potential biotechnological applications. For example, Bromelia karatas fruits contain antioxidants and proteins with bactericidal activity, but studies regarding the activity of these metabolites and potential benefits are required. We evaluated the bactericidal activity of the methanolic extract (treated and not treated with activated charcoal) and its fractions (hexane, ethyl acetate, and methanol) from ripe B. karatas fruit (8 °Brix) against Escherichia coli, Enterococcus faecalis, Salmonella enteritidis, and Shigella flexneri. The methanolic extract (ME) minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined at eight concentrations. The methanolic extract MIC was 5 mg/mL for E. faecalis and 10 mg/mL for the other bacteria; the MBC was 20 mg/mL for E. coli and E. faecalis, and 40 mg/mL for S. enteritidis and S. flexneri. Through gas chromatography–mass spectrometry, 131 compounds were identified, some of which had previously been reported to have biological activities, such as bactericidal, fungicide, anticancer, anti-inflammatory, enzyme inhibiting, and anti-allergic properties. The most abundant compounds found in the ME of B. karatas fruits were maleic anhydride, 5-hydroxymethylfurfural, and itaconic anhydride. This study shows that B. karatas fruits contain metabolites that are potentially beneficial for health.

Recent developments in the use of activated charcoal in medicine

One of the raw forms of graphite is activated charcoal which has an extensive surface area allowing for the adsorption of a wide range of chemicals. It possesses the strongest physical adsorption forces of the available materials, as well as the largest volume of adsorbing porosity. Activated charcoal acts as an adsorbent, collecting and storing substances in the gastrointestinal tract, reducing or blocking absorption in the bloodstream. The ingested toxins interact with charcoal by recycling toxins in the intestinal cavity. In cases where the drug has not been absorbed from the abdominal system, it is recirculated through the liver and intestines or by means of passive diffusion or active secretion. The article aims to review the most recent advances in the use of the activated charcoal, including the dose, how charcoal acts in the body, the mechanism of action, administration, contraindications, as well as the impact of various factors on the adsorption process. In addition, we also discussed numerous medical applications of activated charcoal.

Prevalence of medically unsupervised activated charcoal use a cause for concern in celiac disease?

BACKGROUND

Celiac disease is an autoimmune disorder that causes an intolerance to gluten. Owing to hidden sources, lack of clear labeling, and cross-contamination, it is not uncommon for individuals with celiac disease to inadvertently ingest gluten. A strict gluten-free diet is the only treatment.

OBJECTIVES

The purpose of this study was to identify the frequency of activated charcoal use in celiac disease as a purported remedy despite the lack of literature on the safety and efficacy of the practice and to elucidate the manner in which using activated charcoal as a treatment for acute gluten ingestion is being communicated.

METHODS

Using a descriptive study design, a Web-based survey was sent to members of the celiac disease community via social media pages for voluntary participants 18 years and older diagnosed with celiac disease. Participants were stratified into 3 major groups: (1) those who had heard of using activated charcoal as a remedy to counteract gluten ingestion and used it, (2) those who had heard of using activated charcoal but had not used it, and (3) those who had not heard of using activated charcoal.

RESULTS

In subjects with celiac disease, 424 of 1613 respondents (26%) had heard of using activated charcoal as a potential remedy for gluten ingestion, and 12% had used it. The top source of information regarding any general information including remedies for maladies related to celiac disease was social media networks 72.3% (879/1613). Of those who had used activated charcoal, 122 participants (61.3%) reported subjectively feeling a reduced severity of symptoms.

CONCLUSION

Pharmacists should be aware of the off-label use of activated charcoal for accidental gluten ingestion in celiac disease. Pharmacists should educate patients with celiac disease that there is not sufficient evidence to support the use of activated charcoal.

Fulminant Bacillus cereus food poisoning with fatal multi-organ failure

This case represents a rare fulminant course of fried-rice associated food poisoning in an immunocompetent person due to pre-formed exotoxin produced by Bacillus cereus, with severe manifestations of sepsis, including multi-organ (hepatic, renal, cardiac, respiratory and neurological) failure, shock, metabolic acidosis, rhabdomyolysis and coagulopathy. Despite maximal supportive measures (continuous renal replacement therapy, plasmapheresis, N-acetylcysteine infusion and blood products, and broad-spectrum antimicrobials) and input from a multidisciplinary team (consisting of infectious diseases, intensive care, gastroenterology, surgery, toxicology, immunology and haematology), mortality resulted. This case is the first to use whole genome sequencing techniques to confirm the toxigenic potential of B. cereus It has important implications for food preparation and storage, particularly given its occurrence in home isolation during the COVID-19 pandemic.

The Use of Activated Charcoal to Treat Intoxications

BACKGROUND

In 2016, according to the German Federal Statistical Office, 178 425 cases of intoxication (poisoning) were treated in German hospitals. The poison control centers in the German-speaking countries gave advice in a total of 268 787 instances of poisoning in that year, and use of activated charcoal was recommended in 4.37% of cases. The application of activated charcoal plays a major role in both primary and secondary detoxification. This article serves as an overview of the mechanism of action, indications, contraindications, modes of application, and dosing of activated charcoal.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed. The opinions of experts from the poison control centers in the German-speaking countries were considered in the interpretation of the data.

RESULTS

The administration of activated charcoal is indicated to treat moderately severe to life-threatening intoxication. It should be carried out as soon as possible, within the first hour of the ingestion; timed-release preparations can be given up to 6 hours after the ingestion. An important contraindication is impaired consciousness with the danger of aspiration in a patient whose air- way has not yet been secured. Activated charcoal is ineffective or inadequately effective in cases of poisoning with acids or bases, alcohols, organic solvents, inorganic salts, or metals. The proper dosage consists of an amount that is 10 to 40 times as much as that of the intoxicating substance, or else 0.5-1 g/kg body weight in children or 50 g in adults. Repeated application is indicated for intoxications with agents that persist for a longer time in the stomach and for intoxications with timed-release drugs or drugs with a marked enterohepatic or entero-enteric circulation. The routine combination of activated charcoal with a laxative is not recommended.

CONCLUSION

Even though intoxications are common, there is still no internationally valid guideline concerning the administration of activated charcoal. A precise analysis of the risks and benefits is needed for each administration, and a poison control center should be consulted for this purpose.

The use of biochar in animal feeding

Biochar, that is, carbonized biomass similar to charcoal, has been used in acute medical treatment of animals for many centuries. Since 2010, livestock farmers increasingly use biochar as a regular feed supplement to improve animal health, increase nutrient intake efficiency and thus productivity. As biochar gets enriched with nitrogen-rich organic compounds during the digestion process, the excreted biochar-manure becomes a more valuable organic fertilizer causing lower nutrient losses and greenhouse gas emissions during storage and soil application. Scientists only recently started to investigate the mechanisms of biochar in the different stages of animal digestion and thus most published results on biochar feeding are based so far on empirical studies. This review summarizes the state of knowledge up to the year 2019 by evaluating 112 relevant scientific publications on the topic to derive initial insights, discuss potential mechanisms behind observations and identify important knowledge gaps and future research needs. The literature analysis shows that in most studies and for all investigated farm animal species, positive effects on different parameters such as toxin adsorption, digestion, blood values, feed efficiency, meat quality and/or greenhouse gas emissions could be found when biochar was added to feed. A considerable number of studies provided statistically non-significant results, though tendencies were mostly positive. Rare negative effects were identified in regard to the immobilization of liposoluble feed ingredients (e.g., vitamin E or Carotenoids) which may limit long-term biochar feeding. We found that most of the studies did not systematically investigate biochar properties (which may vastly differ) and dosage, which is a major drawback for generalizing results. Our review demonstrates that the use of biochar as a feed additive has the potential to improve animal health, feed efficiency and livestock housing climate, to reduce nutrient losses and greenhouse gas emissions, and to increase the soil organic matter content and thus soil fertility when eventually applied to soil. In combination with other good practices, co-feeding of biochar may thus have the potential to improve the sustainability of animal husbandry. However, more systematic multi-disciplinary research is definitely needed to arrive at generalizable recommendations.

Ti-Based nanoMOF as an Efficient Oral Therapeutic Agent

Despite the interest in (Zn, Fe, and Zr)-nanoscaled metal-organic frameworks (nanoMOFs) as intravenous drug nanocarriers, their most convenient oral administration has been almost unexplored. In this scenario, an uncharted Ti-nanoMOF is originally proposed here as an oral therapeutic agent, not as a drug delivery system but as an innovative and efficient oral detoxifying agent of the challenge and timeliness salicylate intoxication (e.g., aspirin). Thus, this orally robust and biosafe Ti-nanoMOF is the only porous nanomaterial, among the six tested MOFs, able to adsorb and retain aspirin under the whole gastrointestinal tract, overpassing the capabilities of the current treatment (i.e., activated charcoal). Further, the biodistribution and bioremoval of Ti-nanoMOF have been assessed, proving a bioprotective character with an intact and almost complete removal by feces.

Efficacy of Whole Bowel Irrigation Using Solutions with or without Adsorbent in the Removal of Paraquat in Dogs

1 The efficacy of whole bowel irrigation with a solution containing either polyethylene glycol (PEG) with electrolyte or an adsorbent (Kayexalate™) with a cathartic (sorbitol) was investigated in 18 dogs who had been given 250 mg kg -1 paraquat dichloride via a jejunal tube to eliminate the influence of gastric absorption.

2 Plasma paraquat concentrations 2 and 3 h after the initiation of bowel irrigation and at the end of the study (5 h later) were significantly lower in the bowel irrigation groups than in the control (no bowel irrigation) group.

3 The total body clearances of paraquat in the bowel irrigation groups were significantly greater than in the control group.

4 There were no significant differences between the two different irrigation solution groups in plasma paraquat concentration, the area under the plasma concentration time curve and the total body clearance.

5 In the PEG with electrolyte group, about 70% of the administered dose of paraquat was removed by means of bowel irrigation (n=4).

6 The adjunction of the adsorbent had no beneficial effects.

7 Haemodynamic changes associated with whole bowel irrigation were unremarkable except that right atrial and pulmonary arterial pressures were elevated in the latter part of the study.

Plant poisonings in children in the Czech Republic, 1996-2001

Ingestion of or exposure to potentially poisonous plants is a relatively common presenting complaint in hospital paediatric departments, especially amongst toddlers. We present a retrospective study conducted to review the hospital admissions following acute childhood poisoning with plants in the Czech Republic over a 6-year period from 1996 to 2001. Six university hospital paediatric departments and two local hospital paediatric departments were involved in the study. Information and complete data on the cases were collected on the basis of all hospital medical records and internal hospital database outcomes. A total of 174 plant exposures were analysed to tabulate the list of top species involved in plant poisonings. The aims were to provide classification according to agent frequency, clinical presentations, severity of symptoms expressed, affected age groups and gender of patients and to evaluate the treatment according to patient outcome. The most frequent ingestions were of thorn apple seeds (14.9%), followed by dumb cane exposures (11.5%) and common yew (9.8%). Thorn apple, dumb cane, golden chain and raw beans caused the most serious symptoms. There were no fatalities reported out of the reviewed medical records. Complete data on plant poisoning in children from all over the territory of the Czech Republic are not available; however, we believe that the frequency of causes and the rank of plant species commonly involved are properly reflected in our study.

In vitro analysis of the effect of supplementation with activated charcoal on the equine hindgut

The present study uses in vitro analytical techniques to investigate the effect of activated charcoal on the microbial community of the equine hindgut and the metabolites they produce. Incubations were performed in Wheaton bottles using a 50 ml incubation of a high-energy feed or a low-energy feed, plus bottles with no added food source, together with five levels of activated charcoal (0, 10, 25, 50 or 100 mg per bottle) and fecal samples as a bacterial inoculum. Using this method the rate of gas production, volatile fatty acid and ammonia concentrations, and pH values were analyzed and found to vary depending on the addition of feed, but the activated charcoal had no effect (P>0.05) on any of these. It is already believed that the effect of activated charcoal as a control for toxic substances is at its highest in the foregut or midgut of animals, and therefore should have little impact on the hindgut. The data presented here suggest that if any of the activated charcoal does reach the hindgut, then it has no significant impact on the microbial community present, nor on the major metabolites produced, and so should not have a detrimental effect on the principal site of fermentation in the horse.

Adsorption of desflurane by the silica gel filters in breathing circuits: an in vitro study

Background

During general anesthesia, a heated breathing circuit (HBC) is used to replace the heat and moisture exchange function of the upper airway. One HBC uses an air dryer filter that employs silica gel (SG) as a desiccant. SG is capable of adsorbing many organic compounds. Therefore, we undertook an in vitro study of the adsorption of desflurane by SG filters.

Methods

An HBC was connected to an anesthesia machine, and a test lung was connected to the circuit. The test lung was mechanically ventilated with 2 or 4 L/min of fresh gas flow, with and without the air dryer filter. Desflurane was administered at a 6 vol% on the vaporizer dial setting. The experiment was repeated 15 times in each group. The end-tidal concentrations were measured during the experiments. The air dryer filter weights were measured before and after the experiments, and the times required to achieve the specific end-tidal desflurane concentrations were determined.

Results

Significant differences in the end-tidal concentrations of desflurane were observed between the control and filter groups (P < 0.001). The filter weights increased significantly after the experiments (P < 0.001). The times required to achieve the same end-tidal desflurane concentrations were different with the application of the air dryer filter (P < 0.001).

Conclusions

The adsorption of desflurane with the use of an air dryer filter was verified in this in vitro study. Careful attention is needed when using air dryer gel filters during general anesthesia.

A retrospective review of the prehospital use of activated charcoal

OBJECTIVE

We studied the complications and timing implications of prehospital activated charcoal (PAC). Appropriateness of PAC administration was also evaluated.

METHODS

We retrospectively reviewed prehospital records over 32 months for overdose cases, where PAC was administered. Cases were assessed for amount and type of ingestant, clinical findings, timing of PAC, timing of transport and arrival into the emergency department (ED), and complications. Encounter duration in cases of PAC was compared with that, for all cases during the study period, where an overdose patient who did not receive activated charcoal was transported.

RESULTS

Two thousand eight hundred forty-five total cases were identified. In 441 cases, PAC was given; and complications could be assessed. Two hundred eighty-one of these had complete information regarding timing of ingestion, activated charcoal administration, and transport. The average time between overdose and PAC was 49.8 minutes (range, 7-199 minutes; median, 41.0 minutes; SD, 30.4 minutes). Complications included emesis (7%), declining mental status (4%), declining blood pressure (0.4%), and declining oxygen saturation (0.4%). Four hundred seventeen cases of PAC had documentation of timing of emergency medical service (EMS) arrival on scene and arrival at the ED. Average EMS encounter time was 29 minutes (range, 10-53 minutes; median, 27.9 minutes). Two thousand forty-four poisoning patients were transported who did not receive PAC. The average EMS encounter time for this group was 28.1 minutes (range, 4-82 minutes; median, 27.3 minutes), not significantly different (P =.114).

CONCLUSIONS

Prehospital activated charcoal did not appear to markedly delay transport or arrival of overdose patients into the ED and was generally safe.

Comparative study of the adsorption of acetaminophen on activated carbons in simulated gastric fluid

Samples of commercial activated carbons (AC) obtained from different sources: Norit E Supra USP, Norit B Test EUR, and ML (Baracoa, Cuba) were investigated. The adsorption of acetaminophen, Co = 2500 mg/L, occured in simulated gastric fluid (SGF) at pH 1.2 in contact with activated carbon for 4 h at 310 K in water bath with stirring. Residual acetaminophen was monitored by UV visible. The results were converted to scale adsorption isotherms using alternative models: Langmuir TI and TII, Freundlich, Dubinin-Radushkevich (DR) and Temkin. Linearized forms of the characteristic parameters were obtained in each case. The models that best fit the experimental data were Langmuir TI and Temkin with R(2) ≥0.98. The regression best fits followed the sequence: Langmuir TI = Temkin > DR > LangmuirTII > Freundlich. The microporosity determined by adsorption of CO2 at 273 K with a single term DR regression presented R(2) > 0.98. The adsorption of acetaminophen may occur in specific sites and also in the basal region. It was determined that the adsorption process of acetaminophen on AC in SGF is spontaneous (ΔG <0) and exothermic (-ΔHads.). Moreover, the area occupied by the acetaminophen molecule was calculated with a relative error from 7.8 to 50%.

Effect of charcoal filter on the emergence from sevoflurane anesthesia in a semi-closed rebreathing circuit

PURPOSE

A charcoal filter attached within the anesthetic circuit has been shown to efficiently adsorb halothane or isoflurane, thus hastening anesthetic recovery in low or minimal flow system. This study was intended to demonstrate whether the charcoal filter enhances the recovery time from sevoflurane anesthesia using a semi-closed circuit system.

MATERIALS AND METHODS

Thirty healthy patients scheduled for elective surgery under sevoflurane anesthesia were randomly assigned to the charcoal filter or control group. Upon completion of surgery, the end-tidal concentration of sevoflurane was maintained at 2.0 vol%. A charcoal filter was attached to the expiratory limb of the breathing circuit of charcoal filter group subjects. After sevoflurane was discontinued, ventilation was controlled with the same minute volume as the intra-operative period at a fresh gas flow rate of 5 L·min⁻¹ with 100% O₂. The elimination kinetics of sevoflurane from end-tidal concentration, Bispectral index and times of eye opening and extubation were obtained.

RESULTS

The exponential time constant (τ) of alveolar sevoflurane concentration in the charcoal filter group was significantly shorter than that in the control group (1.7±0.5 vs. 2.5±1.1 min, p=0.008). The charcoal filter hastened rapid eye opening (11.1±3.8 vs. 14.8±3.0 min, p=0.007) and extubation (11.9±3.9 vs. 15.3±3.2 min, p=0.014), compared to the control group.

CONCLUSION

A charcoal filter enhances the recovery from sevoflurane anesthesia with a semi-closed rebreathing circuit.

The population pharmacokinetics of citalopram after deliberate self-poisoning: a Bayesian approach

Defining the pharmacokinetics of drugs in overdose is complicated. Deliberate self-poisoning is generally impulsive and associated with poor accuracy in dose history. In addition, early blood samples are rarely collected to characterize the whole plasma-concentration time profile and the effect of decontamination on the pharmacokinetics is uncertain. The aim of this study was to explore a fully Bayesian methodology for population pharmacokinetic analysis of data that arose from deliberate self-poisoning with citalopram. Prior information on the pharmacokinetic parameters was elicited from 14 published studies on citalopram when taken in therapeutic doses. The data set included concentration-time data from 53 patients studied after 63 citalopram overdose events (dose range: 20-1700 mg). Activated charcoal was administered between 0.5 and 4 h after 17 overdose events. The clinical investigator graded the veracity of the patients' dosing history on a 5-point ordinal scale. Inclusion of informative priors stabilised the pharmacokinetic model and the population mean values could be estimated well. There were no indications of non-linear clearance after excessive doses. The final model included an estimated uncertainty of the dose amount which in a simulation study was shown to not affect the model's ability to characterise the effects of activated charcoal. The effect of activated charcoal on clearance and bioavailability was pronounced and resulted in a 72% increase and 22% decrease, respectively. These findings suggest charcoal administration is potentially beneficial after citalopram overdose. The methodology explored seems promising for exploring the dose-exposure relationship in the toxicological settings.

Influence of activated charcoal on the pharmacokinetics of moxifloxacin following intravenous and oral administration of a 400 mg single dose to healthy males

AIMS

To evaluate the extent to which enterohepatic recycling circulation contributes to moxifloxacin bioavailability in healthy, males by administration of activated charcoal and to evaluate the efficacy of activated charcoal administration in decreasing systemic concentrations of moxifloxacin in the event of overdose.

METHODS

Nine healthy males, mean age 34 years (range 23-45 years) participated in a single centre, randomized, nonplacebo-controlled, three way crossover study. The pharmacokinetics of moxifloxacin in plasma and urine were determined for up to 96 h following a 400 mg single dose randomly administered on three separate occasions with a minimum washout phase of 1 week. Treatment A was 400 mg moxifloxacin IV as a 1 h infusion, treatment B was 400 mg moxifloxacin IV as a 1 h infusion with oral activated charcoal (5 g directly before the start of the infusion, 5 g immediately after the end of the infusion, and 10 g at 2, 4 and 8 h after the start of the infusion), treatment C was 400 mg oral moxifloxacin with activated charcoal (10 g 15 min before and at 2, 4 and 8 h after drug administration). The subjects underwent a series of clinical and laboratory tests.

RESULTS

Single 400 mg doses of moxifloxacin (PO and/or IV) were safe and well tolerated. The bioavailability of moxifloxacin was significantly decreased when given with charcoal (AUC = 35.5 (IV reference) vs 5.40 (PO) vs 28.5 (IV) mg l(-1) h). Concurrently peak concentrations were lowered C(max) = 3.38 (IV reference) vs 0.62(PO) vs 2.97 (IV) mg l(-1)) by approximately 85% (P < 0.05) following oral administration and by 20% after IV treatment (P < 0.05). Bioavailability amounted to 15.4% (95% confidence interval 9.6, 25.0%) for treatment B while it was 80.4% (95% confidence interval 76.3.6, 84.6%) for treatment C. Terminal half-lives were not affected. The kinetics of urinary excretion corroborated these findings.

CONCLUSIONS

The results of this study show that moxifloxacin undergoes pronounced enteric recycling after systemic uptake. In addition, these findings confirm that activated charcoal may be useful in treating moxifloxacin overdose by preventing its absorption.

Acute poisoning: understanding 90% of cases in a nutshell

The acutely poisoned patient remains a common problem facing doctors working in acute medicine in the United Kingdom and worldwide. This review examines the initial management of the acutely poisoned patient. Aspects of general management are reviewed including immediate interventions, investigations, gastrointestinal decontamination techniques, use of antidotes, methods to increase poison elimination, and psychological assessment. More common and serious poisonings caused by paracetamol, salicylates, opioids, tricyclic antidepressants, selective serotonin reuptake inhibitors, benzodiazepines, non-steroidal anti-inflammatory drugs, and cocaine are discussed in detail. Specific aspects of common paediatric poisonings are reviewed.

The frequency of complications associated with the use of multiple-dose activated charcoal

STUDY OBJECTIVE

The objective of this study was to determine the frequency of complications associated with the use of multiple-dose activated charcoal.

METHODS

The study population was drawn from 8 tertiary care hospitals in 4 North American cities. Medical records of all inpatients between March 1993 and March 1998 with a discharge diagnosis of poisoning (International Classification of Diseases, 9th edition, Clinical Modification codes 960-989.9) were reviewed to select patients who had received multiple-dose activated charcoal (defined as > or =2 doses administered within 12 hours). Medical records of patients who received multiple-dose activated charcoal were reviewed for patient demographics and clinical information regarding the occurrence of pulmonary aspiration, gastrointestinal obstruction, hypernatremia, hypermagnesemia, corneal abrasion, and other complications associated with the use of multiple-dose activated charcoal.

RESULTS

We reviewed 6,258 medical records, identifying 878 patients who received multiple-dose activated charcoal. We judged 5 (0.6%; 95% confidence interval [CI] 0.1% to 1.1%) patients to have had clinically significant pulmonary aspiration and none (0%; upper 95% CI 0.3%) to have had gastrointestinal obstruction. None of the patients with pulmonary aspiration died or had residual sequelae recorded. Hypernatremia (peak serum sodium >145 mEq/L [145 mmol/L]) was documented in 53 (6.0%; 95% CI 4.4% to 7.6%) patients, of whom 5 (0.6%; 95% CI 0.1% to 1.1%) had a serum sodium concentration of greater than 155 mEq/L (155 mmol/L). Hypermagnesemia (peak serum magnesium >2.5 mg/dL [1.0 mmol/L]) was documented in 27 (3.1%; 95% CI 2.0% to 4.2%) patients, of whom 3 (0.3%; 95% CI 0.1% to 1.0%) had peak values that were greater than 3.75 mg/dL (1.5 mmol/L). One patient had a corneal abrasion (0.1%; 95% CI 0% to 0.6%). No other complications were identified.

CONCLUSION

Clinically significant complications associated with the use of multiple-dose activated charcoal occur infrequently.

Charcoal is a sensitive, specific, and stable marker for the diagnosis of aspiration in hamsters

The diagnosis of recurrent aspiration in young children is a perpetual challenge because there is no specific gold standard test to be used. The finding of lipid-laden alveolar macrophages in bronchoalveolar lavage (BAL) is a sensitive but nonspecific marker for the diagnosis of aspiration. We conducted a short-term study comparing tracheal instillation of saline, milk, or a milk-charcoal mixture in hamsters. BAL cytology, lipid-laden alveolar macrophage index, charcoal alveolar macrophage index, and lung histology were monitored for 10 d. A long-term study was performed, and hamsters were monitored for 92 d after milk-charcoal tracheal instillation. Baseline animals (n = 4) had no tracheal instillation. Saline- and milk-instilled animals had BAL performed after 1 (n = 4), 3 (n = 4), and 10 (n = 4) d. Milk-charcoal-instilled animals had BAL performed after 1 (n = 4), 3 (n = 4), 10 (n = 4), 30 (n = 2), 58 (n = 2), and 92 (n = 2) d after tracheal instillation. Total cell counts and percent neutrophils in BAL fluid increased significantly and similarly after milk and milk-charcoal instillation on d 1 compared with baseline and saline-instilled animals. Lipid-laden alveolar macrophage index increased significantly only on d 3 after milk and milk-charcoal instillation compared with all days in the saline-instillation group. Charcoal alveolar macrophage index increased significantly after milk-charcoal instillation (d 1-58) from baseline or all days in the saline-instillation group. We conclude that charcoal particles instilled in tracheas of hamsters can be easily identified in BAL fluid and in lung parenchyma for as long as 3 mo after a single instillation and could potentially be used as a sensitive, specific, and stable marker for the diagnosis of aspiration, although the issue of its applicability to humans is still unsolved.

Pediatric toxicologic concerns

Pediatric poisonings account for significant morbidity in the United States each year. Clinicians must keep current with advances in toxicology to be familiar with the latest recommended treatment regimens and antidotes. They also must be familiar in identifying toxidromes and important physical examination findings. Having these skills can enable the clinician to determine who is at risk for significant morbidity or mortality and to provide the appropriate medical care.

Evaluation of administration of activated charcoal in the home

OBJECTIVE

Activated charcoal (AC) is recognized as the treatment of choice for gastrointestinal decontamination after many ingestions. AC use in the home has been limited by concerns that parents would not administer it properly and that children would refuse to take AC. Previous descriptions of home administration have reported mixed results.

METHODS

This was an 18-month consecutive case series of all patients for whom AC administration was recommended in the home. Data collected included AC availability in the home and/or a local pharmacy, success in administration, amount administered, time after ingestion to AC administration, difficulties in administration, adverse effects, age and gender of patient, substance involved in poisoning, and medical outcome. All cases were followed for at least 3 days after the ingestion. Patients who initially had home AC recommendation but who ultimately were treated in the emergency department (ED) served as a comparison group.

RESULTS

Home administration of AC was recommended in 138 cases. A total of 115 individuals (83%) were treated with AC in the home, with no failures to administer AC. Reasons for failure to manage at home were 1) mother preferred ED (8 cases), 2) could not locate AC (7 cases), 3) pharmacy closed for the night (6 cases) and 4) no home telephone for follow-up (2 cases). Time to AC administration after ingestion was a mean of 38 minutes (+/-18.3) for home treatment and 73 minutes (+/-18.1) for ED treatment. Ninety-five percent of home cases received AC in < or =60 minutes versus 33% for ED management. AC was in the home in 11 cases at the time of recommendation. The amount of AC administered was a mean of 12.1 g (standard deviation: 6.9) and a median of 12 g. Eight children (6.9%) who were treated at home vomited after AC versus 3 (13%) who received ED treatment. No aspirations or complications occurred.

CONCLUSIONS

AC can be administered successfully by the lay public in the home. Home use of AC significantly reduces the time to AC administration.

Adsorptive capacity of activated charcoal for rifampicin with and without sodium chloride and sodium citrate

The effects of two saline cathartics (sodium chloride and sodium citrate) on the adsorptive capacity of activated charcoal (AC) for rifampicin were studied. Solutions of rifampicin alone and rifampicin with 7.5 mg/ml cathartic solution were vortex-mixed for 30 s with different quantities of AC. These were incubated for 30 min at 37 degrees C and analyzed for free rifampicin spectrophotometrically at 320 nm. The addition of sodium citrate significantly increased (p<0.05) the adsorptive capacity of AC for rifampicin with a resulting decrease in B-50 values at both the therapeutic and simulated toxic doses. Sodium chloride addition reduced the binding of rifampicin to AC at the toxic doses. The adsorption of rifampicin to activated charcoal, both alone and with the two saline cathartics, obeyed quantity-dependent kinetics. AC may be co-administered with sodium citrate in the management of rifampicin overdose.

In vitro study on fluoxetine adsorption onto charcoal using potentiometry

This in vitro investigation was performed to study the adsorption rate constant as well as the adsorption characteristics of fluoxetine (F) to activated charcoal and its commercial formulation Carbomix powder in simulated gastric (pH 1.2) fluid environment. Ion-selective electrode (ISE) potentiometry, based on the selective, direct and continuous monitoring of F with an F-ISE constructed in our laboratory was used. The method used in the kinetic experiments consists of the rapid addition of a slurry containing the charcoal into the drug solution under stirring and continuous recording of the F-ISE potential until the establishment of equilibrium. The free ionized drug concentration at appropriate time intervals was calculated from the recorded adsorption curve and the apparent adsorption rate constant was estimated assuming pseudo first order kinetics. Within run R.S.D. of the estimates ranged from 0.24 to 11.5%, while between run R.S.D. (n=3-4) ranged from 0.90 to 13.8%. A linear relationship was found between the apparent adsorption rate constants and the amount of charcoal used with slopes (+/-S.D.) for activated charcoal and Carbomix equal to 1.14(+/-0.21) and 0.146(+/-0.009) s(-1)g(-1), respectively. Successive additions of microvolumes of F solution were made into a charcoal slurry with measurement of the F-ISE potential at equilibrium. The maximum adsorption capacity values (+/-S.D.) of activated charcoal and Carbomix were 254.8+/-1.8 and 405+/-41 mg/g, respectively while the affinity constant values (+/-S.D.) were 45.6+/-2.2 and 55.5+/-2.9 l/g, respectively. The adsorption of F to charcoals was rapid and for amounts of charcoal 10 times greater than the amount of the drug, 95% of F was adsorbed within the first 5 min. Relative to the toxic and lethal doses in cases of F intoxications, both types of charcoals tested adsorbed effectively F at gastric pH. Carbomix can be considered as appropriate charcoal formulation for medical treatment in cases of F poisoning.

Formulation of activated charcoal for per os administration to addicted subjects

The objective of this work was to develop a galenic form of activated charcoal appropriate for the needs of clinical toxicology. To preserve the adsorption capacity of charcoal, we developed an extemporaneous preparation of activated charcoal intended for clinical toxicology. To improve the wettability of activated charcoal, we used densification by wet granulation. The presence of a viscosity agent is necessary to ensure the homogeneity of the suspension and its adhesiveness on gastric mucous membrane. Five formulations with different viscosity agents were prepared, and their adsorption capacity, wettability, viscosity, and adhesiveness were studied.

Determination of the adsorption of tramadol hydrochloride by activated charcoal in vitro and in vivo

Although tramadol is one of the most widely used centrally acting analgesics worldwide, no literature is available regarding adsorption of tramadol HCl powder or tablets (Ultram; 50 mg tramadol HCl per tablet) by activated charcoal (AC) for use as potential adjunct treatment of overdose. The present study incorporated a novel combination of in vitro and in vivo methods to investigate this question. Based on a binding curve of tramadol UV absorbance (UV(a); 225 nm) plotted against the amount of AC, the ratio of amount of tramadol completely adsorbed by AC was 0.05 mg/mg. Also based on UV(a), no tramadol was detected in filtrate of slurries in which up to 62 tablets of Ultram were mixed with 50 g AC; 4.6% of unbound tramadol was detected when 100 tablets of Ultram were mixed with AC. The ratio of amount of tramadol completely adsorbed by AC in this test was 0.10. In vivo, co-administration of 0.1 g/ml of AC produced a 13- to 14-fold rightward shift in tramadol's antinociceptive dose-response curve and a 1.6-fold rightward shift in tramadol's lethality dose-response curve.

Acute cyanide poisoning: a case report

A case of attempted homicide by cyanide ingestion is reported. The victim, a 19-year-old woman, unknowingly ingested cyanide and presented to the Emergency Department unresponsive, in shock, and in profound metabolic acidosis. The differential diagnosis of this presentation and the patient's successful treatment are reviewed. The important management issues surrounding the treatment of cyanide poisoning are discussed.

Gastric decontamination performed 5 min after the ingestion of temazepam, verapamil and moclobemide: charcoal is superior to lavage

AIMS

The aim was to study the efficacy of gastric lavage and activated charcoal in preventing the absorption of temazepam, verapamil and moclobemide when gastric decontamination was performed immediately after ingestion of the drugs.

METHODS

Nine healthy volunteers took part in a randomized cross-over study with three phases. The subjects were administered single oral doses of 10 mg temazepam, 80 mg verapamil and 150 mg moclobemide. Five minutes later, they were assigned to one of the following treatments: 200 ml water (control), 25 g activated charcoal as a suspension in 200 ml water or gastric lavage. Plasma concentrations and the cumulative excretion into urine of the three drugs were determined up to 24 h.

RESULTS

The mean AUC(0,24 h) of temazepam, verapamil and moclobemide was reduced by 95.2% (P < 0.01), 92.8% (P < 0.01) and 99. 7% (P < 0.01), respectively, by activated charcoal compared with control. Gastric lavage did not reduce significantly the AUC(0,24 h) of these drugs. The 24 h cumulative excretion of temazepam, verapamil and moclobemide into urine was reduced significantly (P < 0.05) by charcoal but not by gastric lavage. Charcoal reduced the AUC(0,24 h), Cmax and urinary excretion of all three drugs significantly more than lavage.

CONCLUSIONS

Activated charcoal is very effective and gastric lavage can be rather ineffective in preventing the absorption of temazepam, verapamil and moclobemide when the treatment is given very rapidly after ingestion of the drugs, before tablet disintegration has occurred.

The first line of response for people who self-poison: exploring the options for gut decontamination

The trend for increasing numbers of self-poisoning incidents has been noted and a variety of policy initiatives have been launched. Nurses, particularly in emergency room environments occupy a pivotal place in the chain of response to such acts. Any such response needs to be firmly rooted in evidence-based practice yet the initial management of self-poisoning often involves a consideration of procedures, the application of which can vary enormously. This paper offers some contextual information prior to a critical perspective of management modes, namely emesis, lavage, the use of activated charcoal and whole bowel irrigation. A comparison of the relative advantages and disadvantages of each mode precedes suggestions for nursing practice.

American Academy of Clinical Toxicology Practice Guidelines on the Treatment of Ethylene Glycol Poisoning. Ad Hoc Committee

Fomepizole (4-methylpyrazole, 4-MP, Antizol) is a potent inhibitor of alcohol dehydrogenase that was approved recently by the US Food and Drug Administration (FDA) for the treatment of ethylene glycol poisoning. Although ethanol is the traditional antidote for ethylene glycol poisoning, it has not been studied prospectively. Furthermore, the FDA has not approved the use of ethanol for this purpose. Case reports and a prospective case series indicate that the intravenous (i.v.) administration of fomepizole every 12 hours prevents renal damage and metabolic abnormalities associated with the conversion of ethylene glycol to toxic metabolites. Currently, there are insufficient data to define the relative role of fomepizole and ethanol in the treatment of ethylene glycol poisoning. Fomepizole has clear advantages over ethanol in terms of validated efficacy, predictable pharmacokinetics, ease of administration, and lack of adverse effects, whereas ethanol has clear advantages over fomepizole in terms of long-term clinical experience and acquisition cost. The overall comparative cost of medical treatment using each antidote requires further study.

Effect of activated charcoal alone or given after gastric lavage in reducing the absorption of diazepam, ibuprofen and citalopram

AIMS

The efficacy of activated charcoal alone, and gastric lavage followed by charcoal in reducing the absorption of diazepam, ibuprofen and citalopram was studied in healthy volunteers.

METHODS

In a randomized cross-over study with three phases, nine healthy volunteers were administered single oral doses of 5 mg diazepam, 400 mg ibuprofen and 20 mg citalopram, taken simultaneously after an overnight fast. Thirty minutes later, the subjects were assigned to one of the following treatments: 200 ml water (control), 25 g activated charcoal as a suspension in 200 ml water or gastric lavage followed by 25 g charcoal in suspension given through the lavage tube. Plasma concentrations of diazepam, ibuprofen and citalopram were determined up to 10 h.

RESULTS

The AUC(0,10 h) of diazepam was reduced by 27% (P<0.05) by both charcoal alone and charcoal combined with lavage. The increase in plasma diazepam concentration from 0.5 h onwards was prevented by both interventions (P</=0.05), whereas the Cmax of diazepam was not significantly affected by either treatment. The AUC(0, 10 h) of ibuprofen was reduced by 49% (P<0.05) after the combination treatment and by 30% (P<0.05) after charcoal alone, but there was no significant difference between these two treatments. Both charcoal alone and the combination treatment were equally effective in preventing the increase in plasma ibuprofen from 0.5 h onwards (P<0.01). The Cmax of ibuprofen was reduced by 45% (P<0.05) and by 21% (P=NS), respectively. The AUC(0,10 h) of citalopram was reduced by 51% (P<0.05) after both charcoal alone and charcoal combined with lavage, and the Cmax by 52% (P<0.05) and 54% (P<0.05), respectively. The increase in plasma citalopram concentration from 0.5 h onwards was reduced by about 50% (P<0.01) by both interventions.

CONCLUSIONS

Activated charcoal alone and charcoal combined with lavage showed similar efficacy in preventing the absorption of diazepam, ibuprofen and citalopram. These results suggest that gastric lavage needs not be routinely performed before administration of charcoal.

Are kinetic investigations feasible in human poisoning?

Kinetics in human poisoning have gained more importance because of the development of specific and quantitative analytical methods. Despite many pitfalls related to unprecise data in acute poisonings, several studies showed that kinetic parameters, determined by a simple approach, may be helpful for the management. Parameters include plasma elimination half-life, total, renal and hepatic clearances, amounts eliminated by normal routes or by specific treatments. For numerous drugs, spontaneous toxicokinetics and factors of variation could be assessed. These include the dose ingested, the type of poisoning, the age; the symptoms and organ failures; the associated drugs. Kinetic studies have been a major step for the evaluation of treatments such as gastric lavage, oral activated charcoal, haemodialysis, antidotes and have contributed to the understanding of kinetics-dynamics relationships and to the assessment of severity and prognosis criteria. In clinical practice, it is possible by kinetic investigations to select the patients which will really benefit from a treatment such as haemodialysis in lithium poisoning.

A prospective study of acute poisonings in Finnish hospital patients

1. We have carried out a prospective study of all adult patients presenting with acute poisoning during one month to the Helsinki University Central Hospital (Meilahti Hospital). 2. Two hundred and twenty-six cases of acute poisoning (113 males and 113 females) presented to the emergency department. Most cases in both men (66%) and women (67%) involved alcohol. As to drugs, psychotropic agents predominated in both men and women. The frequency of patient presentation peaked between 7 p.m. and 9 p.m. and was lowest between 8 a.m. and 10 a.m. In most cases, the delay from ingestion of the poison to presentation was longer than 4 h. 3. The clinical status of the patients on arrival was generally good; more than half (55%) of them were fully awake. Serious symptoms (e.g. unconsciousness, insufficient respiration necessitating intubation, aspiration, convulsions or hypotension) occurred in 15% of the presentations. There were no fatalities. 4. One hundred and thirty-five patients (60%) received at least one 50-g dose of activated charcoal. However, charcoal was given in 86% of the cases of drug poisoning. Gastric lavage was performed in 112 cases (50%), and 106 cases (47%) involved both gastric lavage and administration of charcoal. Twenty-one patients received antidotes (flumazenil, calcium gluconate or naloxone) and three patients were hemodialysed. 5. Of the 226 cases, 142 (63%) were managed solely in the emergency department. Of the 84 cases admitted to the hospital, eight had to be managed in the intensive care unit. Almost all patients (94%) were discharged within 24 h. 6. In this survey on 226 consecutive cases of acute poisoning, about two-thirds of the cases involved alcohol, while the most common drugs taken were psychotropic agents. The poisoning was mild in the great majority of the cases. Activated charcoal was generally administered in all but trivial cases of drug poisoning.

An in vitro evaluation of fluoxetine adsorption by activated charcoal and desorption upon addition of polyethylene glycol-electrolyte lavage solution

BACKGROUND

In drug overdoses, treatment with activated charcoal is frequently used because of its adsorptive properties. Recently, whole-bowel irrigation with polyethylene glycol-electrolyte lavage solution has been used as a gastrointestinal decontamination procedure for ingestions of toxins not well adsorbed to activated charcoal and for toxins with a delayed absorption phase, although well adsorbed to activated charcoal. While a combined approach using activated charcoal and whole-bowel irrigation could theoretically enhance the efficacy of both modalities, this improvement remains speculative, since data demonstrating its clinical advantage in overdose treatment are lacking. Fluoxetine, a selective serotonin uptake inhibitor, is one of the most frequently prescribed antidepressants. Fluoxetine is well adsorbed onto activated charcoal. This in vitro investigation was undertaken to study: a) the effect of polyethylene glycol, as well as polyethylene glycol-electrolyte lavage solution, on the adsorption of fluoxetine to laboratory grade-activated charcoal and a commercial activated charcoal formulation (Carbomix powder) in simulated gastric (pH= 1.2) and intestinal (pH=7.2) fluid environment; b) whether the order of polyethylene glycol-electrolyte lavage solution addition would have any effect on the adsorption of fluoxetine to activated charcoal.

METHODS

Adsorption of fluoxetine to charcoal in the presence of polyethylene glycol was examined: a) by the simultaneous addition of polyethylene glycol and charcoal to fluoxetine solution and b) by the addition of charcoal to fluoxetine solution and subsequent addition of polyethylene glycol. In both cases, the slurries were incubated at 37 degrees C for 1 hour and filtered. Free fluoxetine concentration was determined in the diluted filtrate by a reversed-phase high-performance liquid chromatography method.

RESULTS

The amount of fluoxetine adsorbed to activated charcoal (or Carbomix) was dramatically decreased at gastric and intestinal pH by the presence of polyethylene glycol or polyethylene glycol-electrolyte lavage solution added either concurrently or sequentially to activated charcoal.

CONCLUSIONS

In cases of fluoxetine overdose, administration of activated charcoal is recommended, while a combined approach using activated charcoal and whole-bowel irrigation with polyethylene glycol-electrolyte lavage solution is not recommended since it causes a significant desorption of the drug from activated charcoal.

Position statement: single-dose activated charcoal. American Academy of Clinical Toxicology; European Association of Poisons Centres and Clinical Toxicologists

In preparing this Position Statement, all relevant scientific literature was identified and reviewed critically by acknowledged experts using agreed criteria. Well-conducted clinical and experimental studies were given precedence over anecdotal case reports and abstracts were not usually considered. A draft Position Statement was then produced and subjected to detailed peer review by an international group of clinical toxicologists chosen by the American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists. The Position Statement went through multiple drafts before being approved by the boards of the two societies and being endorsed by other societies. The Position Statement includes a summary statement for ease of use and is supported by detailed documentation which describes the scientific evidence on which the Statement is based. Single-dose activated charcoal should not be administered routinely in the management of poisoned patients. Based on volunteer studies, the effectiveness of activated charcoal decreases with time; the greatest benefit is within 1 hour of ingestion. The administration of activated charcoal may be considered if a patient has ingested a potentially toxic amount of a poison (which is known to be adsorbed to charcoal) up to 1 hour previously; there are insufficient data to support or exclude its use after 1 hour of ingestion. There is no evidence that the administration of activated charcoal improves clinical outcome. Unless a patient has an intact or protected airway, the administration of charcoal is contraindicated.

Ethylene glycol poisoning: case report of a record-high level and a review

Ethylene glycol is commonly found in automobile antifreeze and a variety of other commercial products. Ingestion of ethylene glycol, either accidentally or in a suicide attempt, is characterized by severe acidosis, calcium oxalate crystal formation and deposition, and a wide variety of end organ effects that may be fatal. We present a case of a patient who ingested a massive amount of ethylene glycol in a suicide attempt and yet survived with minimal sequelae. A comprehensive review of the literature on the pathology and pathophysiology of ethylene glycol toxicity on each organ system is provided, along with information on diagnosis and current treatment recommendations.