Optimal antidotal dose of activated charcoal

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.

Systematic review on the use of activated charcoal for gastrointestinal decontamination following acute oral overdose

INTRODUCTION

The use of activated charcoal in poisoning remains both a pillar of modern toxicology and a source of debate. Following the publication of the joint position statements on the use of single-dose and multiple-dose activated charcoal by the American Academy of Clinical Toxicology and the European Association of Poison Centres and Clinical Toxicologists, the routine use of activated charcoal declined. Over subsequent years, many new pharmaceuticals became available in modified or alternative-release formulations and additional data on gastric emptying time in poisoning was published, challenging previous assumptions about absorption kinetics. The American Academy of Clinical Toxicology, the European Association of Poison Centres and Clinical Toxicologists and the Asia Pacific Association of Medical Toxicology founded the Clinical Toxicology Recommendations Collaborative to create a framework for evidence-based recommendations for the management of poisoned patients. The activated charcoal workgroup of the Clinical Toxicology Recommendations Collaborative was tasked with reviewing systematically the evidence pertaining to the use of activated charcoal in poisoning in order to update the previous recommendations.

OBJECTIVES

The main objective was: Does oral activated charcoal given to adults or children prevent toxicity or improve clinical outcome and survival of poisoned patients compared to those who do not receive charcoal?  Secondary objectives were to evaluate pharmacokinetic outcomes, the role of cathartics, and adverse events to charcoal administration. This systematic review summarizes the available evidence on the efficacy of activated charcoal.

METHODS

A medical librarian created a systematic search strategy for Medline (Ovid), subsequently translated for Embase (via Ovid), CINAHL (via EBSCO), BIOSIS Previews (via Ovid), Web of Science, Scopus, and the Cochrane Library/DARE. All databases were searched from inception to December 31, 2019. There were no language limitations.  One author screened all citations identified in the search based on predefined inclusion/exclusion criteria. Excluded citations were confirmed by an additional author and remaining articles were obtained in full text and evaluated by at least two authors for inclusion. All authors cross-referenced full-text articles to identify articles missed in the searches. Data from included articles were extracted by the authors on a standardized spreadsheet and two authors used the GRADE methodology to independently assess the quality and risk of bias of each included study.

RESULTS

From 22,950 titles originally identified, the final data set consisted of 296 human studies, 118 animal studies, and 145 in vitro studies. Also included were 71 human and two animal studies that reported adverse events. The quality was judged to have a Low or Very Low GRADE in 469 (83%) of the studies. Ninety studies were judged to be of Moderate or High GRADE. The higher GRADE studies reported on the following drugs: paracetamol (acetaminophen), phenobarbital, carbamazepine, cardiac glycosides (digoxin and oleander), ethanol, iron, salicylates, theophylline, tricyclic antidepressants, and valproate. Data on newer pharmaceuticals not reviewed in the previous American Academy of Clinical Toxicology/European Association of Poison Centres and Clinical Toxicologists statements such as quetiapine, olanzapine, citalopram, and Factor Xa inhibitors were included. No studies on the optimal dosing for either single-dose or multiple-dose activated charcoal were found. In the reviewed clinical data, the time of administration of the first dose of charcoal was beyond one hour in 97% (n = 1006 individuals), beyond two hours in 36% (n = 491 individuals), and beyond 12 h in 4% (n = 43 individuals) whereas the timing of the first dose in controlled studies was within one hour of ingestion in 48% (n = 2359 individuals) and beyond two hours in 36% (n = 484) of individuals.

CONCLUSIONS

This systematic review found heterogenous data. The higher GRADE data was focused on a few select poisonings, while studies that addressed patients with unknown and or mixed ingestions were hampered by low rates of clinically meaningful toxicity or death.  Despite these limitations, they reported a benefit of activated charcoal beyond one hour in many clinical scenarios.

Prospective single blinded randomised controlled trial of two orally administered activated charcoal preparations

OBJECTIVES

To compare two activated charcoal preparations (Carbomix and Actidose-Aqua) in terms of amount ingested and incidence of vomiting after ingestion.

METHODS

Single blinded prospective randomised controlled trial.

RESULTS

The mean amount of charcoal ingested was Carbomix 26.5 g, Actidose-Aqua 19.5 g. The mean difference was 7 g (95% confidence interval (CI) 1.5 to 12.4 g). The incidence of vomiting was for the Carbomix 6% and the Actidose-Aqua 8%. The mean difference in vomiting was 2% (95% CI -0.8 to 4.8)

CONCLUSIONS

Carbomix administration results in an increased amount of activated charcoal ingested after oral administration. Rates of vomiting after activated charcoal administration were low when compared with previously reported rates.

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.

Phenobarbital removal characteristics of three brands of activated charcoals: a system analysis approach

The in vivo phenobarbital removal characteristics of three brands of activated charcoal (Actidose, Charcoaid, Superchar) were studied in normal volunteers using a system analysis approach. The subjects received a 200-mg dose of oral or intravenous phenobarbital followed by a single oral dose of 30 g of one of the three charcoals in a randomized crossover design. The relative merits of the three charcoals in enhancing the removal of oral and intravenous phenobarbital were assessed using a system analysis approach. The removal clearance, time to peak (tp), peak removal clearance (Rmax), percentage of dose removed (PCT infinity), and phenobarbital removal clearance (CLr) were calculated for the oral and intravenous treatments. Superchar had a pulse-like effect, with the shortest tp and the largest Rmax. Actidose and Charcoaid had similar effects, with Actidose inducing slightly greater phenobarbital removal. Superchar has the highest surface area and relative percentage of surface hydroxyl groups, whereas Actidose has the lowest surface area and relative percentage of surface hydroxyl groups of the three charcoals studied. Although correlations between the in vitro and the in vivo phenobarbital adsorption characteristics of the three charcoals may be difficult due to the presence of preservatives and palatibility enhancers in the commercial preparations, it appears that the in vivo effectiveness decreases as the surface area and the concentration of surface hydroxyl groups decrease. The proposed system analysis approach requires fewer assumptions than methods based on compartmental or physiologic approaches and has the advantage of describing the phenobarbital removal in a dynamic manner.

Cholestyramine as an adsorbent in acute lindane poisoning: a murine model

STUDY OBJECTIVES

To compare the effectiveness of single-dose cholestyramine versus single-dose activated charcoal in preventing clinical toxicity after acute lindane ingestion.

DESIGN

CD-1 mice received lindane by enteral (gavage) and parenteral (intraperitoneal) routes, followed by enteral administration of either cholestyramine (2.25 g/kg) or activated charcoal (2.25 g/kg), with subsequent observation for convulsions and death.

MEASUREMENTS

The doses of lindane at which 50% of mice developed convulsions (CD50) and at which 50% of mice died (LD50) were established and compared among control, charcoal-, and cholestyramine-treated groups.

RESULTS

For lindane administered by gavage, the differences in the CD50 and LD50 between the control and the activated charcoal groups were not statistically significant. However, a significant difference did exist in both the CD50 and the LD50 between the group receiving cholestyramine and the control group and between the cholestyramine and activated charcoal groups. After IP administration of lindane, the difference in CD50 or LD50 among control, activated charcoal, or cholestyramine groups was not significantly different.

CONCLUSION

In the murine model, cholestyramine is more effective than activated charcoal in preventing absorption of lindane, thus preventing convulsions and death. These data support the need for clinical studies to determine whether cholestyramine may be a more effective treatment than activated charcoal for acute lindane ingestions in human beings.

In vitro and in vivo adsorption studies of diazinon

The in vitro and in vivo adsorption of diazinon to two brands of activated charcoal and locally produced carbon black (N220) has been studied. Solutions of diazinon 10, 20 and 40 micrograms ml-1 were prepared in distilled water and different quantities of adsorbent added. Diazinon-adsorbent slurries were vortex mixed, centrifuged and analysed for free diazinon spectrophotometrically at 241 nm. Small quantities of activated charcoal (AC) and carbon black (CB) showed little or no adsorption of diazinon, while 1000 mg of either AC or CB was able to take up more than 70% at all concentrations of diazinon tested. In acute toxicity tests in mice the optimal adsorbent: diazinon ratio was 8:1 when the animals were treated with 45 mg kg-1 diazinon after immediate, 1, and 3 h post administration of the adsorbent.

Large surface area activated charcoal and the inhibition of aspirin absorption

Activated charcoal's adsorptive capacity, and therefore potential efficacy, is generally related to its surface area. In our study, the efficacy of two activated charcoal preparations, Actidose-Aqua 1,500 m2/g and Super Char, 3,000 m2/g, were compared on the basis of their ability to inhibit aspirin absorption. Twelve healthy male subjects fasted for eight hours before and four hours after a 20 mg/kg oral dose of aspirin. One hour after aspirin dosing, each subject received either no charcoal, 25 g Actidose-Aqua, or 25 g Super Char in a randomized crossover design. Each aspirin dose was separated from the previous dose by at least seven days. Total urine volumes were collected over 12-hour intervals, beginning 12 hours before the aspirin dose and continuing for 72 hours after dosing. Urine salicylate concentration was measured with a colorimetric assay. The fraction of aspirin dose recovered in the urine was 0.96 +/- 0.13, 0.78 +/- 0.18, and 0.50 +/- 0.20 for the control, Actidose-Aqua, and Super Char treatment phases, respectively. In vitro, Super Char was found to bind more salicylic acid than Actidose-Aqua at pH 8.1. We conclude that both activated charcoal preparations significantly reduced the gastrointestinal absorption of aspirin (P less than .05) and that Super Char was significantly more effective than Actidose-Aqua in reducing the gastrointestinal absorption of aspirin (P less than .01).

Toxicodynamic approach to management of the poisoned patient

We recommend a toxicodynamic approach to the management of the poisoned patient. We define the period between ingestion and onset of toxic manifestations (clinical or laboratory) as the preclinical phase, during which the management of the patient necessarily depends solely on the history of ingestion and the predicted toxicity. In the toxic phase during which the patient shows clinical or laboratory evidence of toxicity, the history, clinical status (signs, symptoms, drug levels, laboratory parameters), and toxicodynamics should guide the therapy. In the resolution phase, when the patient shows clinical improvement and declining drug levels, treatment should be based on clinical status. Gastrointestinal decontamination is critical in the first two phases and may be of value during the resolution phase until the body drug burden declines to safe levels. We recommend an aggressive approach to gastrointestinal decontamination, especially in the preclinical phase. With a history of a potentially toxic ingestion of an absorbable drug, an observation period until passage of a charcoal-laden stool should be achieved before discharge of the patient.

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

Activated charcoal has an ability to adsorb a wide variety of substances. This property can be applied to prevent the gastrointestinal absorption of various drugs and toxins and to increase their elimination, even after systemic absorption. Single doses of oral activated charcoal effectively prevent the gastrointestinal absorption of most drugs and toxins present in the stomach at the time of charcoal administration. Known exceptions are alcohols, cyanide, and metals such as iron and lithium. In general, activated charcoal is more effective than gastric emptying. However, if the amount of drug or poison ingested is very large or if its affinity to charcoal is poor, the adsorption capacity of activated charcoal can be saturated. In such cases properly performed gastric emptying is likely to be more effective than charcoal alone. Repeated dosing with oral activated charcoal enhances the elimination of many toxicologically significant agents, e.g. aspirin, carbamazepine, dapsone, dextropropoxyphene, cardiac glycosides, meprobamate, phenobarbitone, phenytoin and theophylline. It also accelerates the elimination of many industrial and environmental intoxicants. In acute intoxications 50 to 100g activated charcoal should be administered to adult patients (to children, about 1 g/kg) as soon as possible. The exceptions are patients poisoned with caustic alkalis or acids which will immediately cause local tissue damages. To avoid delays in charcoal administration, activated charcoal should be a part of first-aid kits both at home and at work. The 'blind' administration of charcoal neither prevents later gastric emptying nor does it cause serious adverse effects provided that pulmonary aspiration in obtunded patients is prevented. In severe acute poisonings oral activated charcoal should be administered repeatedly, e.g. 20 to 50g at intervals of 4 to 6 hours, until recovery or until plasma drug concentrations have fallen to non-toxic levels. In addition to increasing the elimination of many drugs and toxins even after their systemic absorption, repeated doses of charcoal also reduce the risk of desorbing from the charcoal-toxin complex as the complex passes through the gastrointestinal tract. Charcoal will not increase the elimination of all substances taken. However, as the drug history in acute intoxications is often unreliable, repeated doses of oral activated charcoal in severe intoxications seem to be justified unless the toxicological laboratory has identified the causative agent as not being prone to adsorption by charcoal. The role of repeated doses of oral activated charcoal in chronic intoxication has not been clearly defined.(ABSTRACT TRUNCATED AT 400 WORDS)

The new black magic: activated charcoal and new therapeutic uses

Activated charcoal has been used for centuries as antidotal therapy for poisonings. New variations of charcoal therapy have developed over the last two decades. These modifications include multiple-dose activated charcoal (MDAC) therapy, charcoal hemoperfusion, and a new "superactive" charcoal (SAC). Recent literature suggests using initial charcoal therapy instead of ipecac as a first-line antidotal agent for many acute poisonings. The palatability of charcoal slurries has been enhanced by the addition of carboxymethylcellulose, sucrose, saccharin, chocolate syrup, or sorbitol. The new SAC has shown to adsorb 1.7 to 4 times the amount of substance tested compared with other activated charcoal preparations. Multiple-dose activated charcoal therapy has been shown effective in treating phenobarbital, digoxin, digitoxin, theophylline, and dapsone intoxications, among others. The problems associated with charcoal hemoperfusion therapy have been partially alleviated, and it is now alternative therapy for the seriously intoxicated patient.

Poisoning due to tricyclic antidepressant overdosage. Clinical presentation and treatment

Tricyclic antidepressants are among the commonest causes of both non-fatal and fatal drug poisoning in the world. Their toxicity is due to effects on the brain, the heart, the respiratory system and the parasympathetic nervous system. Symptoms usually appear within 4 hours of an overdose and all but the most seriously poisoned patients recover within 24 hours. The most common clinical features are dry mouth, blurred vision, dilated pupils, sinus tachycardia, pyramidal neurological signs, and drowsiness. In severe poisoning, there may be coma, convulsions, respiratory depression, hypotension and a wide range of electrocardiographic (ECG) abnormalities. The most frequent findings on the ECG are prolongation of the PR and QT intervals; the tracing may resemble bundle branch block or supraventricular or ventricular tachycardias. Treatment of poisoning due to the tricyclic antidepressants is essentially supportive, there being insufficient evidence at present to recommend the use of methods to increase elimination of the drug from the body. Gastric aspiration and lavage should be performed if more than 750 mg of drug have been taken. There must be regular monitoring for hypoxia, acidosis and hypokalaemia and these complications should be corrected enthusiastically. Convulsions should be treated with diazepam or chlormethiazole. Muscular paralysis and artificial ventilation should be employed if anticonvulsants are ineffective. Hypotension should be treated firstly by fluid replacement and then with sympathomimetic agents (dopamine or dobutamine). Antiarrhythmic drugs should only be employed if there is evidence of circulatory failure which fails to respond to correction of hypotension. Sodium bicarbonate infusions should be given to cardiotoxic patients who are acidotic and are worth trying even if the patient is not acidotic. Although physostigmine salicylate will reverse most of the features of tricyclic antidepressant poisoning, its effects are short-lived in serious toxicity and it can produce dangerous side effects; physostigmine should therefore be reserved for those patients who have complications of coma or who have resistant cardiotoxicity or convulsions. Drug screening and quantitative determination of tricyclic antidepressant serum concentrations are useful in a minority of patients who have severe, unusual or prolonged symptoms.

Charcoal and isoniazid pharmacokinetics

Activated charcoal (10 g) administered 1 h after a 600 mg oral dose of isoniazid to six healthy subjects did not reduce the area under the plasma concentration-time curve for isoniazid significantly. Charcoal administration is unlikely to be of value in isoniazid poisoning if delayed by an hour or more after the overdose.

Does alcohol absorb to activated charcoal?

Activated charcoal seldom is used in pure-alcohol poisoning since it is absorbed rapidly from the gut. Furthermore in early reports activated charcoal was found to adsorb alcohol poorly. However, in 1981 North et al. [North, D. S., Thompson, J. D. & Peterson, C. D. (1981). Am. J. Hosp. Pharm., 38, 864-866] demonstrated in dogs that charcoal given at the same time as alcohol can reduce the blood alcohol concentration significantly. To study whether charcoal is of value in a clinical situation, a randomized cross-over study in two phases was conducted. Each person drank 88 g of alcohol and 30 min after either 20 g of activated charcoal was taken or the same volume of water was drunk. There were no significant differences in plasma alcohol concentrations with or without charcoal.

Reduction of diazepam serum half life and reversal of coma by activated charcoal in a patient with severe liver disease

We report a case of prolonged coma (7 days) which arose as a complication of the treatment of alcohol withdrawal seizures and delirium with intravenous phenobarbital and diazepam. In an attempt to enhance the elimination of diazepam and its active metabolites, as well as phenobarbital, 40 grams activated charcoal was given every 4 hours (6 doses). Coma was completely reversed within 12 hours; serum half life (t1/2) of diazepam was reduced from 195 to 18 hours during charcoal administration. We postulate that higher free (unbound) diazepam concentrations secondary to hypoalbuminemia, occurring as a result of liver disease, may have increased the depth of our patient's coma, but paradoxically, by making more drug available for diffusion across the gastrointestinal membrane barrier, may have enhanced the ability of activated charcoal to adsorb diazepam and, therefore, decrease its t1/2.

Gastric lavage

Gastric lavage has been used to manage toxic ingestions since the early 1800s. The entire realm of gastrointestinal decontamination has been extensively studied for the past 30 years. Recommendations are still evolving and remain controversial. The current indications for lavage are obtundation, unprotected airway, seizures, the need for urgent removal, and the tendency to form concretions. Hydrocarbon management depends on specific toxicity and viscosity. Contraindications for this procedure are insignificant ingestions, prolonged time since ingestion, and caustic poisoning. Proper technique minimizes complications and maximizes toxin removal. Activated charcoal and a cathartic are given after lavage. Complications include nasal trauma, esophageal perforation, tracheal intubation, aspiration, electrolyte imbalance, and hypothermia.

Dosage recommendations for activated charcoal-sorbitol treatment

Activated charcoal-sorbitol mixture is used for the treatment of acute poisoning. Based on our experience with healthy adults, overdosed patients and published reports, we have devised a protocol for use of this mixture in different concentrations of sorbitol. The dose is based on the size of the patient, type of poison, and the clinical status. In seriously ill adult patients, we recommend the use of 1 g/kg of activated charcoal in 4.3 ml/kg body weight of 70% sorbitol every 4 hours until the first stool containing charcoal appears. In children and ambulatory adults, the same dose of activated charcoal may be administered in 4.3 ml/kg body weight of 35% sorbitol. Patients requiring multiple doses may be administered activated charcoal as aqueous and sorbitol suspensions alternately every 2-6 hours after the first charcoal stool has appeared. The patients on multiple dose regimen, especially children, should be closely monitored for any fluid or electrolyte imbalance or depletion of essential vitamins.

Effect of charcoal-drug ratio on antidotal efficacy of oral activated charcoal in man

The effect of charcoal-drug ratio on the antidotal efficacy of oral activated charcoal was studied in six healthy volunteers in a randomized cross-over study and compared with the adsorption capacity of activated charcoal in vitro. Aminosalicylic acid (PAS) 1 g and 5 g were ingested on an empty stomach in 30 ml of water. Immediately afterwards the subjects ingested 50 g of activated charcoal in 300 ml of water or 300 ml of water only. PAS 10 g 20 g were only given with 50 g of activated charcoal administered immediately afterwards. The plasma concentrations and the cumulative excretion of PAS into urine were measured for 48 h. Increasing the dose of PAS from 1 g to 20 g reduced the antidotal efficacy of activated charcoal: at a charcoal-drug ratio of 50:1 under 5% of the dose was absorbed but at a ratio of 2.5:1 about 37%. These data correlated well to the saturation of adsorption capacity of charcoal in vitro. To minimize the possibility of saturation of the adsorption capacity of charcoal in acute intoxications where the amount and type of drug taken is usually unknown, large doses (50-100 g) of activated charcoal should be used.

Effect of dose of charcoal on the absorption of disopyramide, indomethacin and trimethoprim by man

The efficacy of various charcoal-to-drug ratios for the absorption of drugs was studied in 6 healthy volunteers and in vitro at two pHs. Disopyramide 200 mg, indomethacin 50 mg and trimethoprim 200 mg were ingested on an empty stomach with 100 ml water. After 5 min the subjects ingested a charcoal suspension in 300 ml--2.5 g, 10 g, 25 g or 50 g of Norit A, or 10 g of PX-21, or water 300 ml only. Increasing the dose of activated charcoal from 2.5 g to 50 g reduced the gastrointestinal absorption of disopyramide and indomethacin from 30-40% to 3-5%, and that of trimethoprim from 10% to 1% of the respective controls. Disopyramide and trimethoprim were best adsorbed by charcoal in vitro at neutral and indomethacin at acid pH, but saturation of the adsorption capacity was apparent at charcoal-to-drug ratios less than 7.5. Combining the in vitro and in vivo results it can be concluded that the dose of activated charcoal to be given in acute intoxication should be as large as possible, because the drug history is often unknown.

Comparison of activated charcoal and gastric lavage in the prevention of aspirin absorption

Effectiveness of initial treatment of aspirin (ASA) overdosage was evaluated by comparing treatment with activated charcoal (AC) to treatment with gastric lavage in combination with AC. Dogs were used as subjects in four experimental groups. All subjects were administered an overdose of 500 mg/kg of ASA. Treatment was performed 30 minutes later on all groups except controls. Treatment with AC alone resulted in a 17% reduction (P greater than .05) of peak plasma salicylate levels compared with controls. When lavage preceded administration of AC, a 37% reduction (P less than .05) occurred. There was a 48% reduction (P less than .025) in plasma salicylate levels when lavage was preceded and followed by administration of AC. This study demonstrates that gastric lavage in combination with AC is more effective in reducing ASA absorption than AC given alone.

An activated charcoal hemoperfusion system for the treatment of barbital or ethylene glycol poisoning in dogs

The efficacy of activated charcoal (AC) hemoperfusin therapy was studied in dogs acutely poisoned with lethal doses of barbital or ethylene glycol (EG). Two of three barbital-poisoned dogs treated with AC hemoperfusion survived; the dog tha died was only hemoperfused for 1.5 h. Although AC hemoperfusion of EG-poisoned dogs reduced the blood level of the toxicant considerably, this was not enough to effect survival. The use of AC hemoperfusion was an effective therapeutic measure for dogs poisoned with lethal doses of barbital. The use of the AC hemoperfusion system with existing drugs of therapy for EG poisoning may be beneficial.

Saline cathartics and saline cathartics plus activated charcoal as antidotal treatments

The results of this experimental study indicate that Na2SO4 reduces the gastrointestinal absorption of aspirin, but not that of pentobarbital, chlorpheniramine, or chloroquine. Activated charcoal (AC) and the combination of AC + Na2SO4 were effective in reducing gastrointestinal absorption of all four test drugs. The combination treatment was more effective than AC treatment in reducing gastrointestinal absorption of aspirin, pentobarbital, and chloroquine. We believe that saline cathartics should not be used in lieu of AC for treatment of poison ingestions, and their routine use to treat poison ingestion should be reevaluated. On the other hand, saline cathartics may be used in conjunction with AC to enhance the antidotal effect of the adsorbent.

Activated charcoal updated

Activated charcoal, commonly recommended for treatment of chemical ingestions, is the residue from destructive distillation of various organic materials treated to increase its adsorptive power. Since there are no known side effects, the dose should be sufficiently large for optimum adsorption. In the literature, the recommended doses range from 30 gm to 120 gm, or in a charcoal-drug ratio of 10:1. For maximum effect, activated charcoal should be administered within 30 minutes of ingestion. It can be given while its effectiveness for a particular toxic substance is verified.