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Drug Interactions between calcium / ferrous fumarate / vitamin d and Eltroxin

This report displays the potential drug interactions for the following 2 drugs:

  • calcium/ferrous fumarate/vitamin d
  • Eltroxin (levothyroxine)

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Interactions between your drugs

Moderate

levothyroxine calcium carbonate

Applies to: Eltroxin (levothyroxine) and calcium / ferrous fumarate / vitamin d

Using calcium carbonate together with levothyroxine may decrease the effects of levothyroxine. You should separate the administration of levothyroxine and calcium carbonate by at least 4 hours. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Moderate

levothyroxine ferrous fumarate

Applies to: Eltroxin (levothyroxine) and calcium / ferrous fumarate / vitamin d

Levothyroxine and ferrous fumarate should not be taken orally at the same time. Products that contain iron may interfere with the absorption of levothyroxine and reduce its effectiveness. You should separate the dosing of these medications by at least 2 to 4 hours if possible. Contact your doctor if your condition changes or you experience symptoms of hypothyroidism such as dry skin, weight gain, cold intolerance, weakness, muscle cramps or stiffness, slow pulse, or constipation. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Moderate

calcium carbonate ferrous fumarate

Applies to: calcium / ferrous fumarate / vitamin d and calcium / ferrous fumarate / vitamin d

Using calcium carbonate together with ferrous fumarate may decrease the effects of ferrous fumarate. Separate the administration of ferrous fumarate at least two hours apart from calcium carbonate. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Drug and food interactions

Moderate

levothyroxine food

Applies to: Eltroxin (levothyroxine)

The timing of meals relative to your levothyroxine dose can affect absorption of the medication. Therefore, levothyroxine should be taken on a consistent schedule with regard to time of day and relation to meals to avoid large fluctuations in blood levels, which may alter its effects. In addition, absorption of levothyroxine may be decreased by foods such as soybean flour, cotton seed meal, walnuts, dietary fiber, calcium, and calcium fortified juices. These foods should be avoided within several hours of dosing if possible. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

When levothyroxine is given during continuous enteral nutrition (tube feedings) for more than 7 days, the tube feeding should be interrupted for at least one hour before and one hour after the dose of levothyroxine. You may need more frequent blood tests to monitor levothyroxine levels.

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Moderate

calcium carbonate food

Applies to: calcium / ferrous fumarate / vitamin d

Calcium absorption may be increased by taking it with food. However, foods high in oxalic acid (spinach or rhubarb), or phytic acid (bran and whole grains) may decrease calcium absorption. Calcium may be taken with food to increase absorption. Consider spacing calcium administration for at least 2 hours before or after consuming foods high in oxalic acid or phytic acid. Talk to your doctor if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Minor

ferrous fumarate food

Applies to: calcium / ferrous fumarate / vitamin d

Consumer information for this minor interaction is not currently available. Some minor drug interactions may not be clinically relevant in all patients. Minor drug interactions do not usually cause harm or require a change in therapy. However, your healthcare provider can determine if adjustments to your medications are needed.

For clinical details see professional interaction data.

Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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