UMEM Educational Pearls - Toxicology

Title: CBD, AST, and ALT

Category: Toxicology

Keywords: cannabinoids, liver enzymes, toxicology (PubMed Search)

Posted: 1/20/2026 by Lena Carleton, MD (Updated: 1/26/2026)
Click here to contact Lena Carleton, MD

Consumer use of cannabidiol (CBD) products for medicinal and recreational purposes has increased in recent years. Regulatory barriers have limited randomized controlled trials examining the clinical and physiologic effects of cannabinoids in humans. This study aimed to evaluate the impact of daily cannabidiol oil use on liver enzymes and endocrine hormones in healthy adults.

In this double-blind, randomized, placebo-controlled study conducted at a clinical pharmacology unit in Wisconsin, 201 healthy adults were randomized to receive either oral CBD (2.5 mg/kg twice daily) or placebo. Laboratory testing was performed weekly.

Among participants receiving CBD (n = 151), 8 developed AST and ALT elevations greater than three times the upper limit of normal; 7 of these also had eosinophilia. No participants in the placebo group (n = 50) developed similar transaminase elevations. There were no significant differences between groups in measured endocrine hormones, including total testosterone, inhibin B, thyroid-stimulating hormone, total triiodothyronine, and free thyroxine.

Limitations included a modest sample size, unequal group sizes, and a relatively short duration of exposure and follow-up.

Key Takeaway: CBD use may be associated with elevations in AST and ALT. However, evidence remains limited, and abnormal liver enzymes should still prompt evaluation for alternative etiologies.

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Title: How good are we at initiating medications for OUD?

Category: Toxicology

Keywords: Opiate use disorder, MOUD, initiation (PubMed Search)

Posted: 1/15/2026 by Robert Flint, MD (Updated: 1/27/2026)
Click here to contact Robert Flint, MD

In this study reviewing data from the American College of Emergency Physicians’ Emergency Quality Network substance use disorder program, EDs prescribed naloxone in 27% of patients discharged after opioid  overdose. Only 7% received ED administered or prescription for buprenorphine, etc. There is a lot of room for improvement in the care we provide for this subset of ED patients.

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Title: Water Beads: Tiny time bombs

Category: Toxicology

Keywords: Water beads, foreign body ingestion, gastrointestinal obstruction (PubMed Search)

Posted: 1/7/2026 by Kathy Prybys, MD
Click here to contact Kathy Prybys, MD

Water beads are a colorful, fun, popular, and widely available product found in children’s toys, stress squeeze balls, arts and crafts supplies, plant hydration products, air fresheners, and first aid ice packs.  

These jelly-like small super-absorbent polymer balls are similar to the material found in diapers and absorb water expanding 100-800 percent of original size.

Pediatric ingestion is by far the most common poisoning exposure route but insertion into ears and nose and aspiration can occur and has led to serious adverse effects. More than 8000  water bead-related ingestion injuries have been treated in U.S. Emergency Departments.

Over the past 10 years, U.S. Poison Centers reported 19,660 exposures with 55% occurring in 2023 alone. In the majority of cases, no clinical effects (~88%) were seen, however in >11% of cases mild to moderate effects (abdominal discomfort, nausea, and vomiting) were reported and severe effects including complete bowel obstruction, necrosis, and surgical intervention in 0.11%.  The Consumer Product Safety Commission reported at least one death of a 10-month-old girl in 2023 due to water bead ingestion.

Ingested water beads quickly pass into the small intestines where they continue to expand over the next few days and can become large enough (especially in children less than 2 year of age) to be unable to pass through the ileocecal valve causing small bowel obstruction requiring surgical intervention.   

There is little data to guide management after ingestion.  The majority of cases have no clinical effects and home observation is appropriate for asymptomatic for patients greater than 2 years. Recommendations from a report of case series and literature review , in patients less than 2 years of age with evidence of ingestion and symptomatic patients include hospitalization, imaging with US or CT, and close monitoring.   CT, ultrasound, and endoscopy are not 100% reliable and often do not visualize these intraluminal foreign bodies.

 In December 2025, the CPSC approved new federal safety standards for water beads toys setting limits on maximum expansion size of beads and amount of allowable acrylamide.

 Safety Center banner with images of water beads in a bowl, a water bead next to a measuring tape, an x-ray showing water beads in a child's intestine, and a child putting their hands in a tub of water beads

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Winter is in full swing and an escape to warmer climes is the only answer for many. That also means enjoying local tropical seafood and associated toxins. How do you differentiate, manage, and properly recognize the ABEM prompt?

Scombroid  - HISTAMINE reaction

  1. Native histidine conversion to histamine due to improper freezing (>40° F)
  2. Mimics seafood allergy
  3. Treat with oral antihistamines. 
  4. Histamine source is external, not internal production as in allergy, so no role for steroids or epinephrine
  5. Buzzwords: mackerel, tuna, bonito, albacore, sardines, anchovies, mahi-mahi, amberjacks, marlin and herring
  6. Buzzwords: spicy, peppery, or bubbly taste; honeycomb appearance of fish skin

Ciguatera -  CIGUATOXIN contaminated reef fish

  1. Phytoplankton produce ciguatoxin. Little fish eat phytoplankton. Big fish eat little fish. Humans eat big fish where toxin has accumulated. 
  2. Symptoms within hours of ingestion. Lasting weeks to years or rarely life-long.
  3. GI: N/V/D, abdominal pain
  4. Neurologic: ataxia, paresthesia, allodynia. Careful of mimicking MS or DCS
  5. No treatment. Supportive care per clinical effects
  6. Endemic in Australia, the Caribbean and the South Pacific islands.
  7. Barracuda, grouper, snapper, parrotfish, moray eels, triggerfish and amberjacks.
  8. Odorless, tasteless and heat-resistant—fish will not taste different, cooking will not prevent intoxication.
  9. Buzzwords: hot/cold sensation inversion; persistent itching worse with skin warming, e.g. from alcohol or exercise

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Title: Nitrous Oxide a dangerous legal High: "Don't Whippet"

Category: Toxicology

Keywords: Nitrous Oxide, Whippit, unregulated psychotropic, inhalant abuse (PubMed Search)

Posted: 12/2/2025 by Kathy Prybys, MD (Updated: 12/3/2025)
Click here to contact Kathy Prybys, MD

  • Nitrous oxide (N2O) aka “laughing gas”, used clinically for its psychotropic properties as an inhalational anesthetic, is one of the most abused inhalants for decades due to its unregulated wide availability and public perception that it is a safe high. Social media trends have popularized use by teens and young adults.
  • Easily purchased online, in groceries stores, gas stations,  smoke and vape shops it is used as a food processing  propellant in steel aerosol containers like whipped cream and available in small canisters marketed as whipped cream chargers called “whippets”.
  • Between January 1, 2014 - Dec 31, 2023, nitrous oxide nearly doubled in exposure rate with a total of 2,322 exposures reported to U.S Poison Centers.  From 2010-2023,  1240 US deaths were reported between the ages of 15-74 attributable to nitrous oxide poisoning.
  • Similar to Ketamine and phencyclidine, nitrous oxide causes antagonism at the NMDA receptor resulting in short lived reversible euphoria and sedation and analgesic effects through the K-opioid receptor.
  • Nitrous oxide fatalities occur primarily due to asphyxiation and oxygen deprivation causing neurologic sequela, hypotension, arrythmias, and death. N2O depresses the sensation of shortness of breath so users may not seek fresh air.
  •  Chronic recreational N2O exposure impedes vitamin B12 function and causes a distinct neurological syndrome manifested by numbness, gait disturbances, loss of coordination, changes in mentation, and loss of bowel and bladder control, and hematologic abnormalities.
  • On June 6, 2025, the FDA issued a public advisory warning consumers not to inhale nitrous oxide products due to potential for severe adverse events if used for recreational nonfood purposes.

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Title: Cyanide Antidote Shortage

Category: Toxicology

Keywords: Cyanide, antidote, hydroxycobalmin, drug shortage (PubMed Search)

Posted: 11/5/2025 by Kathy Prybys, MD (Updated: 1/27/2026)
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Cyanide is one of the deadliest known poisons causing immediate toxic effects and lethality within seconds to minutes. Exposures are rare, most commonly by inhalational route (HCN gas) from structural fires due to combustion of synthetic materials or from ingestion of cyanide salts. Cyanide toxicity can also occur from dermal or parental (sodium nitroprusside) exposure. 

  • Cyanide is a mitochondrial poison act by binding the heme portion of cytochrome oxidase a3 in the electron transport chain halting ATP production from oxygen shifting cellular respiration from aerobic to anaerobic metabolism causing a profound lactic acidosis > 8
  •  Impaired peripheral oxygen delivery and utilization can cause “arterialization” of venous blood (cherry red skin), in which the concentration of venous oxygen resembles that of arterial blood 
  • Clinical effects are profound but nonspecific, most frequently reported include unresponsiveness, respiratory failure, hypotension, cardiac arrest, and seizure
  • There are no pathognomonic clinical symptoms or diagnostic blood tests for cyanide poisoning (good correlation of carboxyhemoglobin levels >10 with cyanide toxicity, lactate level >10), clinical suspicion is required
  • Rapid administration of antidote is crucial. Survival is determined by timing of exposure, rapid recognition, and administration of antidote and supportive treatment. 

The preferred first line antidote is hydroxycobalamin (vitamin B12) available as Cyanokit, which has higher affinity for cyanide than cytochrome oxidase and binds to form harmless cyanocobalamin and is renally excreted. Limited studies reveal good survival rates in noncardiac arrest patients. Hydroxycobalamin has minimal side effects (red skin and urine, increased BP) and is well-tolerated with safer and simpler mechanism of action than Nithiodote (original antidote), containing sodium nitrite (CN preferentially binds methemoglobin to form cyanomethemoglobin) and thiosulfate (provides sulfur to convert cyanide to thiocynate for excretion). Sodium nitrite has numerous adverse effects causing hypotension and methemoglobin (contraindicated in smoke inhalation victims due to concern for carbon monoxide poisoning, G6PD deficiency, preexisting amenia), and hypersensitivity reactions. Sodium thiosulfate has less side effects and augments cyanide excretion but is considered less effective due to its slow onset, short half-life, low volume of distribution, and poor intracellular penetration.  

As of August 2025, the American Society of Health -System Pharmacists (ASHP) Drug Shortage lists Cyanokit as “limited availability” in the U.S. as manufacturing was suspended due to investigation of ongoing quality defect with concern for sterility and endotoxin content. Impacted batches were released and their numbers are listed in an FDA bulletin (see references). Healthcare providers should weigh the potential benefit of using Cyanokit against the risk of infection. Infusion set with 0.2 micron in line filter can be temporarily used for administration of Cyanokit 5 mg hydroxycobalmin to prevent potential infection.

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Title: CO Pulse Oximetry in CO Poisoning

Category: Toxicology

Keywords: Carbon Monoxide, Hyperbaric (PubMed Search)

Posted: 9/26/2025 by TJ Gregory, MD (Updated: 9/29/2025)
Click here to contact TJ Gregory, MD

Carbon Monoxide Poisoning (COP) is a major toxicologic pathology and a common case in the Emergency Department and pre-hospital setting. History is a key component in assessment with the standard diagnostic test being blood gas analysis of Carboxyhemoglobin (COHb). 

Standard pulse oximeter devices are not capable of differentiating oxyhemoglobin from carboxyhemoglobin, leading to the classic pearl that pulse ox may be falsely reassuring in COP. 

In recent years, devices capable of differentiating oxyhemoglobin from COHb have been developed and are fielded in many hospitals and EMS agencies. 

This meta-analysis reviews diagnostic accuracy of pulse CO-oximetry (spCO) devices in comparison to a reference standard COHb blood test. Six studies (1734 patients) were included.

This analysis found that spCO testing has a low sensitivity and high specificity

Pooled sensitivity 0.65 (95% CI 0.44–0.81) 

Pooled specificity 0.93 (95% CI 0.83–0.98)

Pooled LR+ 9.4 (95% CI 4.4 to 20.1)

Pooled LR- 0.38 (95% CI 0.24 to 0.62)

The authors conclude that the low sensitivity precludes use of spCO as an effective screening tool for COP or substitute for COHb. Conversely, we can recognize the utility of the high specificity in identifying patients who do have clinically significant toxicity.  Indeed, the authors discuss potential applications for triage and transport to a hyperbaric oxygen chamber for those who are found to have elevated readings.

Technology advancement and refinement will be interesting to follow. In the meantime, don’t skip the COHb lab just because spCO measurement is reassuring.

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Title: Phenobarbital order set implementation for alcohol withdrawal

Category: Toxicology

Keywords: alcohol withdrawal, phenobarbital, protocol, implimentation (PubMed Search)

Posted: 9/24/2025 by Robert Flint, MD (Updated: 9/25/2025)
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This study looking at pre and post-phenobarbital order set use to treat inpatient alcohol withdrawal syndrome found:

“AWS symptoms resolved more rapidly after implementation, with a 4.2- to 5.0-point reduction in daily maximum CIWA-Ar scores at 24 to 96 hours from hospital presentation, 30.1-hour reduction in AWS treatment duration (95% CI, 16.7-43.5 hours), and 2.2-day reduction in time to hospital discharge (95% CI, 0.7-3.7 days). Safety outcomes did not significantly differ before and after implementation.”

Remember phenobarbital can be used for alcohol withdrawal for our ED patients as well. 

Here is the protocol:

Nursing

Vital signs 10 minutes after phenobarbital loading dose

Clinical Institute Withdrawal Assessment for Alcohol Revised (CIWA-Ar) every 1-4 hours based on score

Loading Dose

Phenobarbital 15 mg/kg intravenous piggyback (recommended for most patients)

Phenobarbital 10 mg/kg intravenous piggyback (low risk or heavily pretreated with benzodiazepines)

As-Needed Doses

Phenobarbital 130 mg intravenous twice as needed for uncontrolled agitation or CIWA-Ar ?15

Phenobarbital 260 mg intravenous once as needed for uncontrolled agitation or CIWA-Ar ?15

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Title: Is it cocaine, fentanyl or amphetamine? Yes.

Category: Toxicology

Keywords: Toxicology, contaminate, opiate, stimulant (PubMed Search)

Posted: 4/5/2025 by Robert Flint, MD (Updated: 1/27/2026)
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This study from Australia reminds us that what patients think they ingested isn’t always what they did ingest. A high percentage of “cocaine” and other stimulants was actually fentanyl or other opiates. The authors do  a nice job referencing similar studies in the United States. Any overdose could be a mixed picture due to impure street drugs.

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This retrospective population cohort study looked at  first time ED visits for adolescents and young adults comparing those with visits related to alcohol to those not related to alcohol. Patients in the alcohol related visit group had  a threefold increased one year mortality rate.  Cause of death was trauma, poisoning by drug and alcohol. Risk factors include being male, age 20-29, history of mental health and having a visit for withdrawal.  

Adolescents and young adults presenting to an emergency department for an alcohol related complaint are high risk for one year mortality and deserve intervention and appropriate referral.

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Title: QRS widening from Bupropion and NaHCO3 administration

Category: Toxicology

Keywords: bupropion, QRS widening, NaHCO3 (PubMed Search)

Posted: 2/15/2024 by Hong Kim, MD (Updated: 1/27/2026)
Click here to contact Hong Kim, MD

Bupropion associated cardiac toxicity widens the QRS complex by inhibiting the cardiac gap junction, not cardiac Na channel blockade. NaHCO3 is often administered when EKG changes are noted. But the effectiveness of NaHCO3 in bupropion toxicity is not well established. 

A retrospective study between 2010-2020 showed, that administration of NaHCO3 only decreased QRS duration by 2 msec (median). The median NaHCO3 administered was 100 mEq. Although this study was limited by the fact that it only had a small sample size of 13, NaHCO3 administration may provide limited clinical benefit in patients with QRS widening from bupropion overdose.

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Title: Fomepizole for acetaminophen overdose?

Category: Toxicology

Keywords: acetaminophen overdose, fomepizole, NAC (PubMed Search)

Posted: 7/19/2023 by Natasha Tobarran, DO (Updated: 1/27/2026)
Click here to contact Natasha Tobarran, DO

Acetaminophen (APAP) is the leading cause of acute liver failure worldwide. Standard treatment for APAP overdose is with N-acetylcysteine (NAC), which is highly effective if given within 8 hours of ingestion.  However, in delayed presenters or massive ingestions patients can still develop hepatotoxicity. Adjunctive therapies can be considered in these cases including augmented NAC dosing, renal replacement, and fomepizole.

A small amount of APAP is metabolized to N-acetyl-p-benzoquinone imine (NAPQI) by cytochrome 2E1. In therapeutic doses, the body is able to detoxify the NAPQI using glutathione. In overdose, glutathione stores get depleted and NAPQI can cause hepatotoxicity. Mitochondrial damage in APAP overdose is mediated by the c-Jun-N-terminal Kinase (JNK) pathway. 

NAC works to replenish glutathione stores and detoxify NAPQI. In large overdoses, increased dosing of NAC may be necessary. Fomepizole is typically used for its alcohol dehydrogenase inhibitor property to treat methanol and ethylene glycol poisoning. Fomepizole is also a cytochrome 2E1 and JNK inhibitor and can be used in APAP overdose to block the formation of NAPQI and mitigate mitochondrial damage.  Dialysis can be used to eliminate APAP from the body completely in massive overdoses or if significant acidosis or renal failure. 

This study is a case series of 14 patients treated for APAP overdose between 2017 – 2021 at a tertiary hospital

  • Patients treated with standard NAC therapy
  • They also received IV fompeizole loading dose of 15 mg/kg followed by 10mg/kg every 12 hours at the discretion of the treating team
  • Most cases received only the loading dose
  • Some cases also received renal replacement therapies
  • Patients had “better than expected outcomes” based on initial presentation, APAP levels, liver function tests, and expected clinical course
  • No unfavorable outcomes
  • No side effects

Limitations of the study:

  • Patients were treated with NAC which is the standard of care
  • No formal protocol for the administration or identification of patients treated with fompeizole

In summary:

  • NAC is the standard of care in acetaminophen poisonings
  • Consider fomepizole as an adjunctive therapy in patients that are critically ill
  • Consult your poison center 1-800-222-1222 or friendly toxicologist for help in identifying these patients

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Age >36

LOC

Prolonged exposure (>24hrs)

COHgb level >25%

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Title: Pediatric edible cannabis toxicity

Category: Toxicology

Keywords: cannabis exposure, pediatric, toxicity, NPDS (PubMed Search)

Posted: 7/6/2023 by Hong Kim, MD (Updated: 1/27/2026)
Click here to contact Hong Kim, MD

Medical Cannabis is permitted in 39 states and Washington DC while 18 sates and Washington DC has legalized recreational cannabis use. As cannabis products become more available, pediatric exposure has also increased.

A retrospective study of National Poison Data System involving children < 6 years from 2017 and 2021 showed: Pre-COVID (2017-2019) & COVID (2020-2021)

  • 7043 exposures: (increase of 1375%)
  • 2017: 207  
  • 2021: 3054 
  • Residential exposure: 97% (n=6842)

Common Clinical effects

  • CNS depression: 70% (n=3381)
    • Pre-COVID: 61.6% --> COVID: 72.9% (p<0.05)
  • Tachycardia: 11.4% (N=548)
    • Pre-COVID: 10.3% -->COVID: 11.6% (p,0.05)
  • Vomiting: 9.5% (n=4827)
    • Pre-COVID: 7.5% -->COVID: 10.0% (p<0.05)
  • Ataxia: 7.4% (n=352)
  • Confusion: 6.1% (n=294)
  • Mydriasis: 5.9% (n=284)
  • Respiratory depression: 3.1%

Disposition

  • Admission: 22.7%
  • Critical care: 8.1% (n=533)
    • Pre-COVID: 6.6% -->COVID: 8.6% (increase of 30%) (p<0.05)
  • Non-critical care: 14.6% (n=1027)
    • Pre-COVID: 9.7% -->COVID: 16.3% (increase of 68%)(p<0.05)

Conclusion

  • Pediatric cannabis exposure has increased between 2017 and 2021. consequently, more pediatrics patients developing toxicity and being hospitalized.

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Title: Falsely Elevated Lithium Levels

Category: Toxicology

Keywords: Lithium, Lab error, Toxicity (PubMed Search)

Posted: 6/15/2023 by Natasha Tobarran, DO (Updated: 1/27/2026)
Click here to contact Natasha Tobarran, DO

Lithium toxicity can present acutely with gastrointestinal symptoms and chronically with neurologic symptoms such as tremor and ataxia. Diagnosis and treatment with normal saline hydration and/or dialysis depends on lithium levels in conjunction with signs and symptoms.

Lithium levels can be falsely elevated when blood samples are collected in green top tubes which contain lithium heparin, or if the blood collection volume is too small.  Not recognizing that a lithium level may be falsely elevated can lead to misdiagnosis as well as unnecessary hospitalizations and treatments. The study by Wills et al found lithium levels as high as 4 mmol/L (therapeutic range 0.6-1.2 mmol/L) in lithium naïve volunteers collected in the wrong tube and with small blood volumes. If a patient has an elevated lithium level in the absence of lithium toxicity symptoms, consider a falsely elevated level and redraw using the appropriate tube and sample size. 

In summary:

  • Ensure the lithium sample is collected in a non heparin containing tube
  • Confirm sufficient sample volume
  • Look at the clinical picture when deciding on treatment for patient
  • Have a low threshold to repeat the lithium level
  • Consult your poison center 1-800-222-1222 or friendly toxicologist

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Title: High dose insulin for calcium channel blockers: amlodipine vs. non-dihydropyridines

Category: Toxicology

Keywords: amlodipine, non-dihydropyridines, high-dose insulin (PubMed Search)

Posted: 6/1/2023 by Hong Kim, MD (Updated: 1/27/2026)
Click here to contact Hong Kim, MD

Calcium channel blocker (CCB) overdose can lead to severe shock/hypotension. A small study was conducted to compare the hemodynamic effects of high-dose insulin (HDI) for two classes of CCB (dihydropyridines vs. non-dihydropyridines) that work differently to manage hypertension.   

Study design:

  • Retrospective study from a single poison center (2019 – 2021)

Study sample:

  • Amlodipine poisoning cases: 18
  • Non-dihydropyridine (non-DHP) poisoning cases: 15

Result

Median number of maximum concomitant vasopressors (p=0.04)

  • Amlodipine: 3 (IQR: 2-5; range 0-6)
  • Non-DHP: 2 (IQR: 1-3; range 0-5)

Median difference in max concomitant vasopressors: 1 (95% CI: 0 – 2)

Median max epinephrine dosing

  • Amlodipine: 0.31 mcg/kg/min
  • Non-DHP: 0.09 mcg/kg/min

Use of rescue methylene blue (p=0.009)

  • Amlodipine: 7/18 (39%)
  • Non-DHP: 0

Conclusion:

  • Amlodipine poisoning on HDI required more vasopressors and higher doses of epinephrine compared to non-DHP (verapamil or diltiazem)
  • This may be due to vasodilatory effect of amlodipine compared to non-DHPs

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Flumazenil is a reversal agent for benzodiazepine overdose.  Adverse events including seizure, agitation and cardiac arrhythmias have been reported but the frequency of adverse events is unknown.

AE and serious AEs were defined as:

AE: 

  • Aggressive behavior, agitation, screaming, restlessness
  • Nausea/vomiting, abdominal cramps
  • Sweating, shivering, chills, hot flashes
  • Headache, dizziness
  • Anxiety, distress, depressed mood, abnormal crying
  • Tremors 

Serious AE (SAE):

  • Seizures
  • Supraventricular arrhythmia
  • Multiple ventricular beats
  • Tachycardia
  • Sudden fall in systolic BP

A systematic review/meta-analyses of 13 randomized controlled trials showed

  • AEs more common in flumazenil group vs. placebo (risk ratio: 2.85; 95% CI: 2.11-3.84)
  • SAEs more common in flumazenil group vs. placebo (risk ratio: 3.81; 95% CI: 1.28-11.39) 

Most common AEs

  • Aggressive behavior, agitation, screaming: 26.2% (n=33/126)
  • Nausea/vomiting, abdominal cramps: 20.6% (n=26/126)
  • Anxiety, distress, depressed mood: 15.7% (n=19/126)

Most common SAEs

  • Supraventricular arrhythmia: 30% (n=4/12)
  • Seizure: 25% (n=3/12)
  • Tachycardia: 25% (n=3/12)

Conclusion

  • Administration of flumazenil to patients with known or suspected benzodiazepine overdose is associated with increased risk of AEs

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Title: Xylazine in heroin/fentanyl

Category: Toxicology

Keywords: xylazine, adulterate, heroin, fentanyl (PubMed Search)

Posted: 12/16/2021 by Hong Kim, MD
Click here to contact Hong Kim, MD

 

Xylazine is a central alpha-2 agonist (similar to clonidine) that is used as a veterinary tranquilizer. It also possesses analgesic, and muscle relaxant properties. Heroin/fentanyl is increasingly being adulterated with xylazine and resulting in severe adverse effects (CNS and respiratory depression, bradycardia, and hypotension), including deaths. 

According to CDC, 0.1%-5.5% of IMF death in US between 2019 – 2020 involved xylazine. 

In Philadelphia, PA:

The detection of xylazine in unintentional overdose death increased from

  • 2010 – 2015: 2%
  • 2016: 11%
  • 2017: 10%
  • 2018: 18%
  • 2019: 31%

Approximately 25% of drug seizures in Philadelphia contained xylazine in 2019

 

There is no effective pharmacologic agent for xylazine toxicity. Similar to clonidine toxicity, high dose naloxone may be tried. But pediatric data show that approximately 50% of pediatric clonidine toxicity response to high-dose naloxone administration. Thus, naloxone administration may not reverse the CNS/respiratory depression, bradycardia and hypotension.

 

Conclusion

  • There is increasing adulteration of heroin/fentanyl with xylazine
  • Naloxone administration may not reverse the toxicity of xylazine

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Substance use disorder contributes significantly to pediatric exposure/poisoning. There has been an increase in the opioid overdose deaths in the US, placing pediatric population to possible exposure. A retrospective study of fatal pediatric poisoning in the US was investigated using the National Violent Death Reporting System (NVDRS) from 2012-2017.

17 US states (AK, CO, GA, KT, MD, MA, NJ, NM, NC, OH, OK, OR, RI, SC, UT, VA, WI) reported to NVDRS from 2012-2017.   

Age was limited to 0-9 years

 

Results

1850 violent deaths were identified: n=122 (7%) were poisoning related

 

Characteristics

  • Male: 49%
  • Approximately 25% were homicide-suicides

Region

  • Midwest: 25%
  • Northeast: 5%
  • South: 53%
  • West: 17%

Most common exposure/etiology

  1. Opioid (50%)
  2. Benzodiazepines (8%)
  3. Amphetamines (7%)
  4. Antidepressants (5%)

Conclusion

  • A large proportion of poisoning related pediatric fatality was due to opioid exposure
  • Largest proportion of death was reported from the Southern US.

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Title: Clinical severity score for acute poisoned patients ICU requirement score (IRS)

Category: Toxicology

Keywords: ICU requirement score, physiologic score system (PubMed Search)

Posted: 8/19/2021 by Hong Kim, MD (Updated: 8/20/2021)
Click here to contact Hong Kim, MD

 

There are several clinical scoring systems (SAPS II, SAPS III, SOFA, etc.) to assess the severity and/or risk of mortality in critically ill patients. However, the routinely used physiologic scoring systems are not always suitable for poisoned patient. 

ICU requirement score (IRS) has been recently developed by investigators from Europe and a validation study (retrospective cohort) has been performed.

ICU requirement score (IRS) components (see inserted table)

  • Age
  • Systolic blood pressure
  • Heart rate
  • GCS
  • Type of intoxication
  • Comorbidities (dysrhythmia, cirrhosis, and/or respiratory insufficiency, secondary diagnosis requiring ICU admission)

Retrospective cohort 

  • Study duration: Jan 1, 2009 to Dec 31 ,2019
  • Positive IRS score: >= 6
  • Comparison to SAPS II, SAPS III, SOFA score, and PSS
  • End point: need for ICU treatment

Results

N=1503

Area under the curve for IRS ROC: 0.736 (95% CI: 0.702-0.770)

IRS <6

  • Negative predictive value: 95% (95% CI: 93-97)
  • Positive predictive value: 21% (95% CI: 18-24)
  • Sensitivity: 89% (95% CI: 85-93)
  • Specificity: 38% (95% CI:36-41)

Conclusion

  • IRS of < 6 demonstrated excellent negative predictive value for ICU admission.
  • A larger study of ICU requirement score will be needed to further assess its usefulness/limitation prior to clinical use.  

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