Does propranolol interact with eletriptan (Eletriptan) or rizatriptan (Rizatriptan)?

Propranolol Interaction with Eletriptan and Rizatriptan

When prescribing rizatriptan to patients taking propranolol, the dose should be reduced to 5 mg (instead of the standard 10 mg) due to a significant pharmacokinetic interaction, while no dose adjustment is needed when prescribing eletriptan to patients on propranolol. 1, 2

Rizatriptan and Propranolol Interaction

Propranolol significantly affects the metabolism of rizatriptan through the following mechanisms:

• Propranolol inhibits monoamine oxidase-A (MAO-A), which is responsible for metabolizing rizatriptan 2
• This inhibition leads to approximately 70% increase in plasma AUC and a four-fold increase in some individuals 1
• The FDA-approved drug label for rizatriptan specifically warns about this interaction 1

Clinical Recommendations for Rizatriptan + Propranolol:

• Reduce rizatriptan dose to 5 mg when used concurrently with propranolol 1
• This dose reduction is necessary regardless of the propranolol dosage 2
• The interaction occurs even with attempts to separate administration times 2

Eletriptan and Propranolol Interaction

Unlike rizatriptan, eletriptan does not have a clinically significant interaction with propranolol:

• The FDA label for eletriptan states that propranolol increases eletriptan's Cmax and AUC by only 10% and 33%, respectively 3
• These modest increases do not require dose adjustment 3
• The label specifically states: "No dosage adjustment appears to be needed for patients taking propranolol" 3

Specificity of Beta-Blocker Interactions

It's important to note that this interaction is specific to propranolol and not a class effect of all beta-blockers:

• Other beta-blockers like nadolol and metoprolol do not significantly alter rizatriptan pharmacokinetics 2
• The 2002 American Family Physician guideline specifically lists propranolol as a contraindication/precaution for rizatriptan but not for other triptans 4
• The interaction is due to propranolol's specific ability to inhibit MAO-A, which other beta-blockers do not share 2

Clinical Implications and Monitoring

When managing patients on both medications:

• Monitor for increased triptan-related side effects such as dizziness, drowsiness, chest pressure, and throat tightness 4
• Be aware that the rizatriptan-propranolol interaction is pharmacokinetic (affecting drug levels) rather than pharmacodynamic (affecting blood pressure response) 2
• No serious adverse events have been reported from the combination when appropriate dose adjustments are made 2

Common Pitfalls to Avoid

1. Failing to reduce rizatriptan dose when co-prescribed with propranolol
2. Assuming all beta-blockers interact similarly with triptans
3. Unnecessarily avoiding eletriptan in patients taking propranolol
4. Attempting to manage the rizatriptan-propranolol interaction by separating administration times (this strategy is ineffective) 2

This evidence-based approach ensures safe and effective management of migraine in patients requiring both triptan therapy and propranolol.