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Drug Interactions between Flomax and Verelan PM

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

  • Flomax (tamsulosin)
  • Verelan PM (verapamil)

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Interactions between your drugs

Moderate

verapamil tamsulosin

Applies to: Verelan PM (verapamil) and Flomax (tamsulosin)

Verapamil may increase the blood levels and effects of tamsulosin. This can cause blood pressure to fall excessively and heart rate to increase, especially when you rise from a sitting or lying position. The risk of other side effects such as dizziness, lightheadedness, fainting, headache, flushing, nasal congestion, heart palpitations, and priapism (prolonged and painful erection unrelated to sexual activity) may also increase. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Let your doctor know if you develop these symptoms while using tamsulosin and they do not go away on their own or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medication affects you, and use caution when getting up from a sitting or lying position. 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

verapamil food

Applies to: Verelan PM (verapamil)

You may take verapamil with or without food, but take it the same way every time. You should avoid consuming grapefruit or grapefruit juice as much as possible during treatment with verapamil. If you have been regularly consuming grapefruit or grapefruit juice with verapamil, do not increase or decrease the amounts of these products in your diet without first talking to your doctor. Grapefruit juice can increase the blood levels and effects of verapamil. Contact your doctor if you experience sudden, unexplained weight gain; swelling of the hands, ankles, or feet; chest pain; or difficulty breathing. Avoid driving or operating hazardous machinery until you know how the medication affects you, and use caution when getting up from a sitting or lying position. 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

tamsulosin food

Applies to: Flomax (tamsulosin)

Food may affect the intestinal absorption of tamsulosin. You should take tamsulosin approximately one-half hour following the same meal each day to ensure steady absorption and blood levels of the drug.

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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.

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.