What is the interaction between apixaban and consumption of cider vinegar or pickled foods?

Apixaban and Cider Vinegar/Pickled Foods Interaction

There is no documented clinically significant interaction between apixaban and cider vinegar or pickled foods. Based on the available evidence, consumption of cider vinegar or pickled foods does not affect the metabolism, absorption, or efficacy of apixaban.

Pharmacokinetics of Apixaban and Potential for Food Interactions

Apixaban is a direct factor Xa inhibitor with the following key pharmacokinetic properties:

• Absorption: Approximately 50% bioavailability 1
• Metabolism:
  • 25% hepatically metabolized, primarily via CYP3A4 2
  • Also minor metabolism via CYP1A2, 2C8, 2C9, 2C19, and 2J2 enzymes 2
• Elimination:
  • Multiple pathways including metabolism, biliary excretion, and direct intestinal excretion
  • Only about 27% of total apixaban clearance occurs via renal excretion 2, 1
• Drug transport: Substrate for P-glycoprotein (P-gp) transporter 2

Food Effects on Apixaban

The available evidence indicates that:

• Food does not have a clinically meaningful impact on apixaban bioavailability 1
• Unlike rivaroxaban, apixaban can be taken with or without food 2, 3
• There are no specific warnings regarding vinegar or pickled foods in any of the guidelines 2

Clinically Significant Interactions with Apixaban

The main interactions to be concerned about with apixaban are:

1. Strong dual inhibitors of CYP3A4 and P-gp:

   • These can significantly increase apixaban plasma levels 2
   • Examples include cyclosporine, ketoconazole, and certain HIV protease inhibitors 2

2. Strong inducers of CYP3A4 and P-gp:

   • These can significantly decrease apixaban plasma levels 2
   • Examples include rifampin, carbamazepine, phenytoin, and St. John's wort 2

3. Medications affecting hemostasis:

   • Concomitant use with antiplatelet agents, NSAIDs, or other anticoagulants increases bleeding risk 4

Vinegar and Pickled Foods

Neither cider vinegar nor pickled foods are known to:

• Inhibit or induce CYP3A4 enzymes
• Affect P-glycoprotein transport
• Contain significant amounts of vitamin K (unlike some green leafy vegetables that can affect warfarin)

Clinical Recommendations

1. Patients can safely consume cider vinegar and pickled foods while taking apixaban without concern for altered drug efficacy or increased bleeding risk.

2. Monitor for these actual high-risk interactions instead:

   • Strong CYP3A4 and P-gp inhibitors (e.g., ketoconazole, itraconazole) 2
   • Strong CYP3A4 and P-gp inducers (e.g., rifampin, carbamazepine) 2
   • Medications affecting hemostasis (e.g., aspirin, NSAIDs) 4

3. Important dosing considerations for apixaban:

   • Dose reduction is required if the patient meets two or more of these criteria: age ≥80 years, body weight ≤60 kg, or serum creatinine ≥1.5 mg/dL 5
   • Dose reduction is also required when used with strong dual inhibitors of CYP3A4 and P-gp 2

Common Pitfalls to Avoid

1. Don't confuse apixaban with rivaroxaban: Unlike rivaroxaban, apixaban does not need to be taken with food for optimal absorption 2

2. Don't overlook actual drug interactions: While focusing on food interactions, be vigilant about medications that truly interact with apixaban, particularly strong CYP3A4/P-gp inhibitors or inducers 2

3. Don't miss dose adjustment criteria: Approximately 12-17% of apixaban prescriptions may be inappropriately dosed 5, often due to misapplication of the dose reduction criteria

In conclusion, patients taking apixaban can consume cider vinegar and pickled foods without concern for drug interactions. Clinical focus should remain on monitoring for interactions with medications that affect CYP3A4 and P-gp pathways.