Eltrombopag, sold under brand names like Promacta and Revolade, is a medication used to increase platelet counts in individuals with certain blood disorders, such as chronic immune thrombocytopenia (ITP) and severe aplastic anemia. To ensure this medication works as intended, patients must be aware of significant dietary restrictions, particularly concerning foods high in calcium and other minerals that can interfere with its absorption. The core of this restriction is based on the principle of chelation, where polyvalent cations in foods and supplements bind to the drug in the gastrointestinal tract, preventing it from being properly absorbed into the bloodstream.
The Calcium Rule: Dairy and Fortified Products
The most critical food group to manage is anything containing high levels of calcium (more than 50 mg). This is because calcium is a polyvalent cation that readily chelates with eltrombopag, drastically reducing its bioavailability. A key part of managing your diet while on this medication is timing. You should take eltrombopag at least two hours before or four hours after consuming any food item that meets this high-calcium threshold.
Dairy Products to Avoid or Time Properly
Dairy is a primary source of calcium and must be carefully scheduled around your medication dose. Items to watch out for include:
- Milk and milkshakes
- Cheese (especially hard cheeses)
- Yogurt
- Ice cream
- Butter (some brands)
Fortified Foods and Drinks to Consider
Many products are fortified with extra vitamins and minerals, including calcium. Always check nutrition labels carefully. Examples include:
- Calcium-fortified juices (e.g., orange juice)
- Fortified cereals
- Fortified soy milk, almond milk, and other dairy alternatives
- Some energy or protein bars
The Mineral Trap: Supplements and Antacids
Beyond just food, other oral products containing polyvalent cations can have the same inhibitory effect on eltrombopag absorption. It is imperative to separate your eltrombopag dose from these items by at least four hours.
Supplements to Delay
- Multivitamins with Minerals: Many contain calcium, iron, and magnesium. Take your multivitamin at a different time of day than your eltrombopag dose.
- Calcium Supplements: Tablets or chews designed to boost calcium intake are a major source of interference.
- Iron, Magnesium, Zinc, and Selenium Supplements: These can also bind to the drug and must be avoided within the four-hour window.
Medications to Avoid Concurrent Use With
- Antacids: Over-the-counter and prescription antacids often contain aluminum, magnesium, or calcium carbonate. Take your antacid at least four hours away from your eltrombopag dose.
- Certain Heartburn Medications: Always consult with your doctor or pharmacist about any new medication, especially for stomach issues.
Making it Work: A Low-Calcium Diet Approach
If scheduling your meals and medication is difficult, a simple solution is to eat a low-calcium meal with your eltrombopag. A low-calcium meal contains less than 50mg of calcium. This means you can still eat, just not calcium-rich items. For example, a meal of scrambled eggs, unfortified soy milk, and fruit is a perfectly acceptable breakfast with eltrombopag.
Comparison of High-Calcium vs. Low-Calcium Meals with Eltrombopag
| Feature | High-Calcium Meal | Low-Calcium Meal |
|---|---|---|
| Calcium Content | > 50 mg | < 50 mg |
| Example Breakfast | Yogurt with granola and fruit, latte | Scrambled eggs, coffee, plain toast |
| Example Lunch | Cheese sandwich, glass of milk | Grilled chicken salad with oil and vinegar dressing |
| Meal Timing | Must be taken at least 4 hours away from eltrombopag | Can be eaten with eltrombopag |
| Bioavailability Impact | Significantly reduced | No significant impact |
| Patient Convenience | Requires strict scheduling | Offers more flexibility with timing |
| Risk of Reduced Efficacy | High if timing is not followed | Low |
Example Strategies for Scheduling
Many patients find it easiest to take their eltrombopag dose first thing in the morning with a low-calcium breakfast, such as plain toast and black coffee, or on an empty stomach an hour before a calcium-rich meal. Another common strategy is to take the medication before bed, after the last meal of the day, to create a large buffer zone. It's important to establish a routine that fits your lifestyle to ensure consistent and effective treatment.
Conclusion
Properly managing your diet and supplement intake is a critical component of successful eltrombopag therapy. High-calcium foods like dairy products, fortified beverages, and mineral supplements can severely hamper the drug's absorption, rendering it less effective. By following the recommended four-hour separation rule, or opting for low-calcium meals around your dose, you can ensure the medication provides the maximum therapeutic benefit. Always consult your healthcare provider or pharmacist for personalized advice and to clarify any concerns about your dietary intake while on eltrombopag.
