Gabapentinoid poisoning: Rapid overview of emergency management

To obtain emergency consultation with a medical toxicologist, in the United States, call 1-800-222-1222 for the nearest regional poison control center. Contact information for poison control centers around the world is available at the WHO website and in the UpToDate topic on regional poison control centers (society guideline links).

Clinical features

Isolated gabapentinoid (gabapentin, pregabalin) overdoses typically cause only mild somnolence, dizziness, and/or ataxia. Vital signs are typically in a normal range.

Less common clinical findings can include:

Myoclonus
Visual and/or auditory hallucinations, agitation, paranoia
Seizures – If occurring, these typically last several minutes and resolve without intervention
Rhabdomyolysis
Significant CNS depression (eg, coma) – Can occur in massive overdose, acute or chronic kidney impairment, or co-ingestion of other sedatives

Toxicity can develop from therapeutic dosing in chronic kidney disease given primarily renal elimination.

Co-ingestion with other substances (eg, opioids) is common.

Long-term gabapentinoid therapy can lead to the development of tolerance, dependence, and withdrawal symptoms with cessation of therapy.

Diagnostic evaluation

All symptomatic patients

Fingerstick blood glucose
Serum electrolytes, creatinine, creatine kinase
Serum acetaminophen, salicylate, and ethanol concentrations to rule out these common co-ingestions
Electrocardiogram to screen for poisoning by drugs that affect the QRS or QTc intervals
Pregnancy test in females of childbearing age

Treatment

Supportive care

CNS depression – Most patients with isolated gabapentinoid poisoning recover uneventfully with supportive care without specific intervention. Tracheal intubation may be required if the patient is unable to protect their airway.

Decreased respiratory rate and somnolent – Adults and adolescents: naloxone 0.2 to 2 mg IV/IM or 4 mg IN (children <5 years or ≤20 kg: 0.1 mg/kg/dose IV/IM [maximum dose 2 mg] or 4 mg IN; children ≥5 years or >20 kg: 2 mg IV/IM or 4 mg IN). Naloxone would not be expected to reverse the effects of the gabapentinoid itself but may improve mental status or respiration if the patient has concomitant opioid intoxication, which are common co-ingestants.

Tachycardia and/or hypotension (uncommon) – IV isotonic saline or lactated Ringer (10 to 20 mL/kg, maximum dose 1 L) boluses.

Seizures (for dosing, timing, and alternative medications for refractory seizures, refer to UpToDate content on convulsive status epilepticus) – Antiseizure medications are typically not needed since most seizures are self-limited and brief. For recurrent or prolonged seizures, benzodiazepines are first-line therapy: eg, lorazepam 4 mg IV (children: 0.1 mg/kg IV, maximum dose 4 mg).

Routine gastrointestinal decontamination with activated charcoal for isolated gabapentinoid ingestion is typically not needed since intoxication will improve with supportive care.

Extracorporeal removal

Hemodialysis effectively clears gabapentin and pregabalin and shortens duration of toxicity. It should be performed in a patient with severe gabapentinoid poisoning (eg, coma or respiratory failure with need for mechanical ventilation) and severe kidney impairment (refer to UpToDate content for specific criteria).

CNS: central nervous system; IM: intramuscular; IN: intranasal; IV: intravenous; WHO: World Health Organization.

Graphic 141754 Version 3.0

خرید پکیج

Gabapentinoid poisoning: Rapid overview of emergency management