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Drug Interactions between Fareston and Synthroid

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

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Interactions between your drugs

No interactions were found between Fareston and Synthroid. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.

Fareston

A total of 383 drugs are known to interact with Fareston.

Synthroid

A total of 211 drugs are known to interact with Synthroid.

Drug and food interactions

Moderate

levothyroxine food

Applies to: Synthroid (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

toremifene food

Applies to: Fareston (toremifene)

You should avoid drinking grapefruit juice during treatment with toremifene. Grapefruit juice may increase the blood levels of toremifene. This can make you more likely to develop side effects such as vaginal bleeding, blood clots, or an irregular heart rhythm that may be serious or life-threatening. Contact your doctor if you experience potential signs and symptoms of blood clots such as chest pain, shortness of breath, sudden loss of vision, and pain, redness or swelling your arms or legs. You should also seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, or fast or pounding heartbeats during treatment with toremifene.

Talk to your doctor before using toremifene with soy products. There is some evidence that substances present in soy may stimulate breast tumor growth and interfere with the action of toremifene, although this has not been proven. Whether soy products are effective for hot flashes is also uncertain. 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 food

Applies to: Synthroid (levothyroxine)

Using multivitamin with minerals together with levothyroxine may decrease the effects of levothyroxine. You should separate the administration of levothyroxine and multivitamin with minerals 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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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.


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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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