Potential pharmacobezoar formation of large size extended-release tablets and their dissolution - an in vitro study.

OBJECTIVE: Extended release (ER) tablets/capsules in massive ingestion overdoses are prone to form pharmacobezoars potentially increasing the risk of late-appearing toxic effects and prolonged symptoms. Oral activated charcoal is often sufficient to prevent drug absorption, but in a recent massive ingestion of highly toxic substances, prior orogastric lavage might be considered. The disintegration characteristics of ER preparations in overdose situations is valuable to understand if the time line and course of the intoxication might be prolonged, but information on these characteristics are unavailable. Slow disintegration and/or pharmacobezoar formation, and the large size makes ER preparation impossible to evacuate using a 30F orogastric lavage tube. This study evaluates the disintegration and pharmacobezoar formation of a simulated massive ER tablet ingestion in an in vitro model, using a selection of extended release tablets, with different disintegrating characteristics when present in therapeutic numbers. Furthermore, the sizes of the formed pharmacobezoars were compared with the dimensions of a 30F orogastric lavage tube. METHOD: A standardized model mimicking the physical effects on pharmaceutical preparations in simulated gastric fluid (SGF) was developed and tested on three mono-depot ER tablets (quetiapine/Seroquel®XR 50 mg, paracetamol/Pinex®Retard 500 mg, verapamil/Isoptin®Retard 240 mg), one poly-depot ER tablet (carbamazepine/Tegretol®Retard 200 mg), and one immediate-release tablet (paracetamol/Panodil® 500mg). Thirty tablets were placed in polyamide mesh bags, either together in one bag or in separate bags, immersed in 1 L SGF, and incubated at 37 °C for 48 h. Released drugs were quantified at 0.5-48 h. RESULTS: Visual inspection showed that Seroquel®XR, Pinex®Retard, and Isoptin®Retard tablets formed firm pharmacobezoars stable for more than 4 h and intact fractions remained for up to 24 h. Drug releases were reduced by 53%, 40%, and 31%, respectively, for up to 8 h compared to separated tablets. Light microscopy showed that contact with SGF transformed the coating of Seroquel®XR and Pinex®Retard to a diffusion-controlled swelled gel-layer, and the Isoptin®Retard tablets into a rigid and slow-releasing matrix. Tegretol®Retard disintegrated into microspheres within 30 min, and Panodil® disintegrated within minutes. DISCUSSION: The developed pharmacobezoars of mono-depot ER tablets demonstrated prolonged drug release. Neither the formed pharmacobezoars, nor the single tablets of the tested mono-depot ER preparations, would pass through the lumen of a standard orogastric lavage tube, rendering this modality ineffective for tablet removal in gastrointestinal decontamination.

Availability of Paracetamol Sold Over the Counter in Europe: A Descriptive Cross-Sectional International Survey of Pack Size Restriction.

Due to the risk of hepatotoxicity when excessive amounts of paracetamol are consumed, Poisons Information Centers (PICs) frequently receive paracetamol-related enquiries. This study examined how widely pack size restrictions of paracetamol sold over the counter have been implemented in Europe and also availability of paracetamol through non-pharmacy outlets and their possible associations with frequency of poisoning enquiries. A cross-sectional European multi-centre questionnaire study was performed using a questionnaire to identify the extent and nature of paracetamol pack size restrictions, non-pharmacy outlet sales and the frequency of paracetamol-related enquiries to PICs. In total, 21 European countries participated. All PICs provided telephone hotline services. In 14 (67%) countries, pack size restrictions had been implemented in pharmacies (range: 8-30 g). No significant difference (median difference 0.7%, p-value = 0.36) was found when comparing median frequencies of paracetamol-related enquiries in countries with pack size restriction to countries without restrictions. A significantly lower median frequency of paracetamol-related enquiries was found in countries without non-pharmacy outlet sales compared to those with such sales (median difference 2.2%, p = 0.02). Pack size restrictions on pharmacy sales of paracetamol have been implemented in two-thirds of examined countries. There was no difference in the proportion of paracetamol-related enquiries to PICs among countries with and without pack size restrictions. However, a lower rate of paracetamol-related enquiries was noted in countries where paracetamol was not available in non-pharmacy outlets.

Recreational drug use at a major music festival: trend analysis of anonymised pooled urine.

OBJECTIVE: The spread of new psychoactive substances (NPS) has expanded rapidly in the last decade. The complexity of the pharmacological effects of NPS challenges the traditional treatment guidelines, and information of the emergence of new arrivals is valuable. Our knowledge on the actual range of recreational drugs used and NPS available in Denmark is limited as identification is possible only when consumers become patients in the healthcare system or through drug seizures. We aimed to detect classical recreational drugs and NPS in the urine of music festival attendees and evaluate if the use of NPS could have been predicted by comparing study data with drug seizure data from the previous year published by European and Danish health authorities. METHODS: In a cross-sectional study, 44 urine samples were collected from three urinals at Roskilde Festival 2016-the largest Danish music festival. Two urinals were placed at music stages with late-night concerts, and one urinal was placed at a camp site. Samples were prepared using enzymatic hydrolysis followed by cationic and anionic solid phase extraction, and analysed using ultra performance liquid chromatography-high-resolution time-of-flight mass spectrometry (UPLC-HR-TOF-MS). Data were processed using an in-house library of 467 target substances, including legal and illegal drugs and metabolites. Urine drug-screening immunoassays were also evaluated and results were compared to UPLC-HR-TOF-MS results. RESULTS: In total, 77 drugs, including metabolites, were qualitatively identified in the 44 urine samples. The recreational drugs identified were amphetamine (n = 30), cocaine (n = 44), MDA (n = 40), MDMA (n = 44), THC-COOH (n = 19) and ketamine (n = 17). No NPS were identified. Sample testing using the urine drug-screening immunoassays showed presence of cocaine (n = 27), methamphetamine/MDMA (n = 4), THC (n = 7), "Spice" (n = 7) and methylphenidate (n = 1). These discrepancies might be caused by differences in cut-off values between the analytical methods, limited specificity or cross-reactivity of the urine drug-screening immunoassays compared to UPLC-HR-TOFMS results. CONCLUSION: Widespread uses of classical recreational drugs were identified in pooled urine samples. The prevalence of NPS was not as comprehensive as expected based on the European and Danish health authorities reports on illegal drugs. Urine drug-screening immunoassays results are advised to be confirmed by chromatographic bioanalysis.

Oesophageal Obstruction from a Pharmacobezoar Resulting in Death.

Formation of an intestinal pharmacobezoar is a rare condition. It may form after intake of various oral pharmaceutical preparations of drugs, both as a result of an acute overdose and through chronic use of therapeutic doses of a drug. We report a case with a patient presenting with an oesophageal pharmacobezoar and complete obstruction of the oesophagus and severe toxic symptoms and death related to oral ingestion of multiple drugs.

Comparison of the adsorption capacities of an activated-charcoal--yogurt mixture versus activated-charcoal--water slurry in vivo and in vitro.

BACKGROUND: An activated charcoal--yogurt mixture was evaluated in vivo to determine the effect on the gastrointestinal absorption of paracetamol, as compared to activated-charcoal--water slurry. The potential advantage of the activated-charcoal--yogurt mixture is a better palatability and general acceptance by the patients without loss of efficacy. In addition, paracetamol adsorption studies were carried out in vitro to calculate the maximum adsorption capacity of paracetamol to activated-charcoal--yogurt mixture. METHODS: In vivo: A randomized crossover study on 15 adult volunteers, using paracetamol 50 mg/kg as a simulated overdose. Each study day volunteers were given a standard meal 1 h before paracetamol, then 50 g activated charcoal 1 h later in either of two preparations: standard water slurry or mixed with 400 mL yogurt. Paracetamol serum concentrations were measured using HPLC. The areas under the concentration-time curve (AUC) of the two preparations were compared and used to estimate the efficacy of each preparation. The palatability of both preparations was evaluated using a visual-analogue scale where the volunteers were asked to evaluate the appearance, smell, flavor, texture, ability to swallow, and overall impression of the mixtures. The time spent to consume the activated charcoal was also registered. In vitro: Activated charcoal, simulated gastric (pH 1.2) or intestinal (pH 7.2) fluid, and paracetamol were mixed with yogurt followed by 1 h incubation. The maximum adsorption capacity of paracetamol to activated charcoal was calculated using Langmuir's adsorption isotherm. Paracetamol concentration was analyzed using HPLC. RESULTS: In vivo there was no significant difference (p > 0.05) in the AUC of paracetamol between the two activated-charcoal preparations. Geometric mean values and 95% CI for the AUCs were (in mg/l x min): 6307 (4932-8065) for the activated charcoal--water slurry and 6525 (5111-8330) for the activated charcoal--yogurt mixture. The palatability study showed significant difference (p < 0.05) only in duration of administration, in favor of the activated charcoal--water slurry. In vitro the maximum adsorption capacity of activated charcoal with added yogurt was 544 mg paracetamol/g activated charcoal (pH 1.2), and 569 mg paracetamol/g activated charcoal (pH 7.2). CONCLUSION: The two activated-charcoal preparations showed equal (NS) absorption reduction of paracetamol in vivo. Mixing activated charcoal with yogurt rather than water prolonged the ingestion time, but did not improve the palatability in adults. The presence of yogurt reduced the adsorption capacity in vitro by 9-13% (p < 0.05) compared to control without yogurt (previous study with the same setup).

Subacute fat-embolism-like syndrome following high-volume intramuscular and accidental intravascular injection of mineral oil.

OBJECTIVE: We present a rare case of subacute fat-embolism-like syndrome (FES-like) following intravascular injection of mineral oil-steroid solution with delayed diagnosis, acute onset of pulmonary distress, and transient clinical deterioration. CASE REPORT: A 40-year-old man was admitted following as a pedestrian being hit by a car. Examinations revealed sternum fracture and lung contusion. The patient was discharged with oral analgesics. Seven days later he returned presenting with coughing, hemoptysis, elevated leucocytes, and increased C-reactive protein. Chest radiograph revealed basal infiltrations. Suspecting pneumonia, the patient was discharged with antibiotics. Unknown to the clinicians, the patient had self-administered a mineral oil with added anabolic steroids by intramuscular injections for cosmetic purposes. The patient had observed blood on aspiration, and then relocated the needle before injecting 140 ml in his biceps muscle. Shortly after, the patient described near fainting and hemoptysis suggesting an accidental intravascular injection. Over the next 3 days the patient experienced increasing shortness of breath and hemoptysis. Examinations confirmed the diagnosis and the patient was treated with organ-specific supportive measures, tranexamic acid, and prednisolone and discharged after 11 days in the hospital. CONCLUSION: Subacute FES-like was associated with injection of body filler in muscle tissue. FES-like can mimic pneumonia, posttraumatic lung injury, and other more frequent causes to respiratory failure.

A nationwide register-based survey of baclofen toxicity.

To study the use and misuse (poisonings) of baclofen in the time period of 2007-2012 and to evaluate the severity and clinical symptoms of poisonings including ingested baclofen. The National Patient Register (NPR) was searched for admissions due to baclofen poisonings from 2007 to 2012. The search was conducted with ICD-10 codes for poisoning, self-harm and suicide, and coupled with the baclofen ATC code. All enquiries about baclofen to the Danish Poison Information Centre (DPIC) in the same period were evaluated. Demographic and clinical data were extracted, and the poisonings were classified according to the Poison Severity Score. The number of baclofen poisonings did not increase from 2007 to 2012. Thirty-eight admissions with baclofen poisoning were registered at the NPR; however, only one-third of the reviewed DPIC cases were registered at the NPR with the correct coding. In the group of severely poisoned patients (PSS 3), three patients had only ingested baclofen (mean 2000 mg; SD 500 mg) and eight patients had ingested baclofen together with alcohol or psychotropic drugs (mean 900 mg; SD 641 mg). All patients presented with deep coma and respiratory depression. Additionally, seizures and cardiovascular events (mild hypo- or hypertension and bradycardia) occurred. There is a substantial degree of underreporting of baclofen poisonings in Denmark. Symptoms of baclofen poisoning progress very fast, and toxicity was observed even with doses as low as 150 mg. We therefore recommend that observation and treatment of these patients should be carried out in an intermediate- or intensive care unit. The most important treatment is the maintenance of a protected airway and respiration.

Adherence to international recommendations for gastric lavage in medical drug poisonings in Denmark 2007-2010.

OBJECTIVE: Recent reviews strongly discourage the routine use of gastric lavage in oral poisonings, but the authors suspected that gastric lavage might still be in widespread use in Denmark. We wished to estimate the extent to which gastric lavage in cases of medical drug poisoning, reported in inquiries to the Danish Poison Information Centre (DPIC) from 2007 to 2010, was performed according to international recommendations and whether adherence to recommendations improved over the period. METHODS AND MATERIALS: Inquiries from hospital and emergency departments (EDs) concerning medical drug poisonings were identified in the DPIC database. Patients receiving gastric lavage prior to inquiry were identified, and demographic and poisoning characteristics were retrieved. Indication for gastric lavage was determined from a predefined set of criteria. RESULTS: 10 740 inquiries from hospitals and EDs were identified, of which 1091 cases received gastric lavage. In logistic regression, the frequency of lavage fell significantly from 13.5% in 2007 to 7.9% in 2010 (odds ratio (OR) 0.547, confidence interval (CI) 0.455-0.659). All criteria for gastric lavage were fulfilled in 60 lavaged cases (5.5%), and the fraction did not improve significantly over the period (OR 1.717, CI 0.791-3.724). No individual criterion for lavage showed consistent improvement over the period. CONCLUSION: Gastric lavage is still widely used in Denmark, mostly on questionable grounds where the procedure is unlikely to be beneficial. Recommendations for gastrointestinal decontamination may need to be promoted more actively, and clinicians should be encouraged to seek toxicological advice before performing gastric lavage.

A computerised sampling strategy for therapeutic drug monitoring of lithium provides precise estimates and significantly reduces dose-finding time.

The clinical benefit of implementing Bayesian approach for lithium drug monitoring was evaluated. Intervention group (N = 42) and historical control group (N = 55) patients were each divided into two groups: Dosage with immediate-release lithium carbonate or a sustained-release formulation, lithium citrate. Bayesian approach was performed in the intervention groups, and estimation of lithium steady-state trough concentration was obtained from non-steady-state blood sample, collected about 12 hr after the first lithium study dose. The estimate was compared with the actually measured steady-state concentration. In the control group, lithium monitoring was traditionally performed as steady-state blood sampling. Predicted and measured lithium concentrations were comparable. The desired lithium dose was reached significantly faster in the intervention group compared to control; 2.47 ± 2.22 days versus 9.96 ± 11.24 days (mean ± S.D.) (p = 0.0003). Bayesian approach was an advantage for the clinicians as a fast and safe aid to obtain the optimal lithium treatment dose.

Combined paracetamol and amitriptyline adsorption to activated charcoal.

Objectives. High-gram drug doses seen in multiple-drug poisonings might be close to the adsorption capacity of activated charcoal (AC). The aim was to determine the maximum adsorption capacities (Q(m)) of amitriptyline and paracetamol, separately and in combination, to AC. Methods. ACs (Carbomix® and Norit Ready-To-Use) were tested in vitro. At pH 1.2 and pH 7.2, 0.250 g AC and paracetamol and/or amitriptyline were mixed and incubated. The AC: drug ratios were 10:1, 5:1, 3:1, 2:1, and 1:1. The mixed-drug adsorption vials contained the same AC: paracetamol ratios, but amitriptyline was added as fixed dose (0.080 g) to all samples. Drug concentrations in the liquid phase were analyzed using high-performance liquid chromatography (HPLC)/UV-detection. Results. Q(m), amitriptyline, were 0.49 g/g Carbomix® and 0.70 g/g Norit Ready-To-Use, and Q(m), paracetamol, were 0.63 g/g Carbomix® and 0.72 g/g Norit Ready-To-Use. The tested pH differences had minor effect on the adsorption. The mixed-drug adsorption showed about 40% Q(m) reduction of each drug with increasing amounts of drug/g AC, but the total gram of drug adsorbed to AC was increased compared to one-drug conditions. Conclusion. The adsorption of the two compounds to AC seems to compete resulting in lower maximum adsorption capacity for both drugs when mixed. However, a great adsorptive capacity was noted and might be explained by adsorption of the drugs to different AC surface sites. Furthermore, the Norit Ready-To-Use preparation, with less volume and total weight for the same AC dose as Carbomix®, showed a higher Q(m). This might be clinically significant in terms of preventing nausea, vomiting, and subsequent aspiration.

Dose-dependent adsorptive capacity of activated charcoal for gastrointestinal decontamination of a simulated paracetamol overdose in human volunteers.

The amount of activated charcoal needed to treat drug overdoses has arbitrarily been set at a charcoal-drug ratio of 10:1. Recent in vitro studies have shown a larger adsorptive capacity for activated charcoal when used in a model of paracetamol overdose. In the present study, we investigated whether this reserve capacity exists in vivo. This is clinically relevant in cases of large overdoses or if the full standard dose of 50 g activated charcoal cannot be administered. We performed a randomized, cross-over study (n = 16). One hour after a standard breakfast, 50 mg/kg paracetamol was administered, followed 1 hr later by an activated charcoal-Water slurry containing 50 (control), 25 or 5 g activated charcoal. The areas under the serum concentration-time curve (AUC) for paracetamol were used to estimate the efficacy of each activated charcoal dose. The AUC of the 25-g dose was found to be of similar size compared to the control, although statistics were weak. The AUC of the 5-g dose was 59% larger than the AUC of the 50-g dose (p = 0.0003). The terminal elimination half-life (t(1/2)) of paracetamol was 1.6 (CI 1.4-2.0) and 1.9 (CI 1.5-2.4) hr for 50 and 25 g, respectively (NS), and 2.5 (CI 1.8-3.0) hr for the 5-g dose (p = 0.003). The decrease in t(1/2) of paracetamol for the two larger activated charcoal doses indicates a possible effect of activated charcoal on paracetamol clearance and warrants further investigation. The large adsorptive reserve capacity of activated charcoal in vitro could not be reproduced for the smallest dose of activated charcoal. An activated charcoal-drug ratio of 10:1 is therefore still recommendable.

Effect of ethanol and pH on the adsorption of acetaminophen (paracetamol) to high surface activated charcoal, in vitro studies.

BACKGROUND: Paracetamol (acetaminophen) intoxication often in combination with ethanol, is seen commonly in overdose cases. Doses of several grams might be close to the maximum adsorption capacity of the standard treatment dose (50g) of activated charcoal. The aim of this study was to determine the maximum adsorption capacity for paracetamol for two types of high surface-activated charcoal [Carbomix and Norit Ready-To-Use (not yet registered trademark in Denmark) both from Norit Cosmara, Amersfoort, The Netherlands] in simulated in vivo environments: At pH 1.2 (gastric environment), at pH 7.2 (intestinal environment), and with and without 10% ethanol. METHODS: Activated charcoal, at both gastric or intestinal pHs, and paracetamol were mixed, resulting in activated charcoal-paracetamol ratios from 10:] to 1:1. In trials with ethanol, some of the gastric or intestinal fluid was replaced with an equivalent volume of ethanol, resulting in an ethanol concentration of 10% v/v. After incubation, the concentration of unabsorbed paracetamol was analyzed by high-performance liquid chromatography. The maximum adsorption capacity of paracetamol to activated charcoal was calculated as mg paracetamol adsorbed/g activated charcoal, using Langmuir's isotherm. RESULTS: Carbomix [95% confidence limits are shown in square brackets]: 623.7 [612.8;634.5] mg paracetamol adsorbed/g activated charcoal (pH 1.2), 626.2 [611.6;640.9] mg paracetamol adsorbed/g activated charcoal (pH 7.2); Norit Ready-To-Use: 693.6 [676.8;710.5] mg paracetamol adsorbed/g activated charcoal (pH 1.2), 722.6 [687.4;757.9] mg paracetamol adsorbed/g activated charcoal (pH 7.2). For experiments with ethanol (10% v/v) the results with Carbomix were 465.7 [449.2;482.2] mg paracetamol adsorbed/g activated charcoal (pH 1.2), 498.6 [481.8;515.6] mg paracetamol adsorbed/g activated charcoal (pH 7.2); with Norit Ready-To-Use: 617.2 [606.6;627.7] mg paracetamol adsorbed/g activated charcoal (pH 1.2), 640.6 [624.9;656.4] mg paracetamol adsorbed/g activated charcoal (pH 7.2). CONCLUSION: Under conditions simulating immediate treatment with charcoal, a standard dose of 50 g of either of the two tested activated charcoals adsorbed a sufficient amount of paracetamol to be beneficial in the treatment of the majority of overdoses of this drug. For both types of activated charcoal, with or without ethanol, there was no significant difference in the adsorption of paracetamol at pH 1.2 and 7.2. Norit Ready-To-Use had a larger maximum adsorption capacity than Carbomix, and was not as sensitive as Carbomix to environmental changes (pH and ethanol). The presence of 10% ethanol lowered the adsorption capacity of the two tested activated charcoal preparations by an amount that might be clinically relevant in cases of intoxications by high-gram doses.

The effect of food and ice cream on the adsorption capacity of paracetamol to high surface activated charcoal: in vitro studies.

The effect of added food mixture (as if food was present in the stomach of an intoxicated patient) or 4 different types of ice cream (added as a flavouring and lubricating agent) on the adsorption of paracetamol (acetaminophen) to 2 formulations of activated charcoal was determined in vitro and compared with results from previous investigations showing a maximum adsorption capacity to the two activated charcoal-water slurries at about 0.62-0.72 g paracetamol/g activated charcoal. Activated charcoal (Carbomix or Norit Ready-To-Use), simulated gastric (pH 1.2) or intestinal (pH 7.2) fluid, and paracetamol were mixed with either food mixture or ice cream followed by one hr incubation. The maximum adsorption capacity of paracetamol to activated charcoal was calculated using Langmuirs adsorption isotherm. Paracetamol concentration was analyzed using high pressure liquid chromatography. In the presence of food, the paracetamol adsorption capacity of the 2 activated charcoals was reduced by max. 19% (P<0.05) for Carbomix(R) and by max. 11% (P<0.05) for Norit Ready-to-use compared to control without food (Hoegberg et al. 2002). Depending on which type of ice cream was mixed with the charcoal, the reductions compared to control (Hoegberg et al. 2002) varied between 11% and 26%. Even though a reduction in drug adsorption to activated charcoal was observed when food mixture or ice cream was added, the remaining adsorption capacity of both types of activated charcoal theoretically was still able to provide an effective gastrointestinal decontamination.