Is baclofen (GABA receptor agonist) safe to use in a patient with an upper gastrointestinal (GI) bleed?

Baclofen Safety in Upper GI Bleeding

Baclofen can be safely used in patients with upper gastrointestinal bleeding, as there is no evidence in the guidelines that it worsens bleeding or interferes with standard management protocols for GI bleeds.

Rationale for Safety

The comprehensive consensus guidelines for managing nonvariceal upper GI bleeding 1 do not list baclofen as a contraindicated medication or as a risk factor for worsening bleeding outcomes. The guidelines thoroughly discuss pharmacotherapy options but do not mention GABA receptor agonists like baclofen as medications of concern.

Management Priorities in Upper GI Bleeding

When managing a patient with upper GI bleeding who requires baclofen:

1. Continue standard GI bleed management:

   • Resuscitation with IV fluids 2, 3
   • Blood transfusion if hemoglobin < 7 g/dL 2, 4
   • Early administration of proton pump inhibitors 1, 3
   • Endoscopy within 24 hours of presentation 3, 4

2. Medication considerations:

   • Proton pump inhibitors are the primary pharmacological intervention recommended for upper GI bleeding 1, 5
   • H2-receptor antagonists are not recommended (Grade D recommendation) 1
   • Somatostatin and octreotide are not recommended for routine management (Grade C recommendation) 1

Why Baclofen Can Be Continued

• Baclofen works primarily on GABA-B receptors in the central nervous system
• Unlike NSAIDs, anticoagulants, or antiplatelet agents, baclofen does not have known mechanisms that would:
  • Impair platelet function
  • Affect clotting cascade
  • Increase gastric acid production
  • Damage gastric mucosa

Important Clinical Considerations

• Avoid abrupt discontinuation: Sudden withdrawal of baclofen can cause severe complications including seizures, hallucinations, and autonomic instability
• Monitor for side effects: Nausea and vomiting from baclofen could potentially complicate assessment of ongoing bleeding
• Feeding considerations: For patients on baclofen with upper GI bleeding, follow standard feeding protocols based on the cause of bleeding 6:
  • For high-risk lesions (Forrest I-IIb ulcers or variceal bleeding): wait 48 hours after endoscopic therapy
  • For low-risk lesions: feeding can resume as soon as tolerated

Conclusion

While the guidelines don't specifically address baclofen in upper GI bleeding, the absence of this medication from the list of concerning drugs, combined with its mechanism of action that doesn't directly impact gastric mucosa or hemostasis, suggests it can be safely continued. The priority should remain on standard management with proton pump inhibitors, appropriate resuscitation, and timely endoscopy.