Treatment of Gabapentin Overdose
Gabapentin overdose should be managed primarily with supportive care, with hemodialysis reserved for severe cases with significant renal impairment or life-threatening symptoms requiring mechanical ventilation. 1
Clinical Presentation of Gabapentin Overdose
Gabapentin overdose typically presents with:
- Central nervous system depression
- Slurred speech
- Double vision
- Drowsiness
- Lethargy
- Diarrhea
- Ataxia (difficulty coordinating movements)
- Labored breathing
In severe cases, patients may develop:
- Coma
- Respiratory depression
- Altered mental status
Management Algorithm
1. Initial Assessment and Stabilization
- Secure airway, breathing, and circulation
- Obtain vital signs
- Assess level of consciousness
- Determine time and amount of ingestion if possible
2. Primary Treatment: Supportive Care
- Supportive care is the mainstay of treatment for gabapentin overdose 1
- Monitor vital signs and neurological status
- Provide respiratory support as needed
- Maintain hydration with IV fluids
- Consider activated charcoal only if presentation is within 1 hour of ingestion and airway is protected
3. Contact Poison Control Center
- Call 1-800-222-1222 for case-specific guidance 1
- Poison centers can provide expert treatment recommendations for specific poisoning cases 2
4. Extracorporeal Treatment (ECTR) Considerations
For patients with normal kidney function:
- ECTR is generally not recommended (weak recommendation, very low quality of evidence) 3
For patients with decreased kidney function AND coma requiring mechanical ventilation:
- Consider hemodialysis (weak recommendation, very low quality of evidence) 3
- Gabapentin can be effectively removed by hemodialysis 1
Special Considerations
Severity Assessment
Most gabapentin overdoses have a relatively benign clinical course 4, but fatal cases have been reported 5. The FDA label notes that acute oral overdoses of gabapentin up to 49 grams have been reported with patients recovering with supportive care 1.
Monitoring Parameters
- Neurological status (level of consciousness, pupillary response)
- Respiratory function (rate, depth, oxygen saturation)
- Cardiovascular parameters (blood pressure, heart rate)
- Renal function (especially important as gabapentin is primarily excreted by the kidneys)
High-Risk Populations
- Patients with renal impairment: Gabapentin elimination is significantly reduced, leading to higher plasma concentrations and prolonged half-life (up to 132 hours in dialysis patients compared to 5-9 hours in those with normal renal function) 6
- Elderly patients: May have higher sensitivity to CNS effects
- Patients with underlying respiratory conditions
Complications to Monitor
- Falls or fractures: Increased risk with gabapentin use, especially at doses ≥2,400 mg/day 7
- Altered mental status: Risk increases at doses 600-2,399 mg/day 7
Prognosis
With appropriate supportive care, most patients with gabapentin overdose recover completely without sequelae. The FDA label notes that "all patients recovered with supportive care" in reported overdose cases 1. However, severe cases, particularly in patients with renal impairment, may require more aggressive intervention including hemodialysis.