Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, cimetidine may prevent your body from processing your calcium channel blocker properly.
What might happen:
The effects of your calcium blocker may increase.
What you should do about this interaction:
If you experience weakness, fatigue, dizziness, or a fast heartbeat, contact your doctor. It may be necessary to adjust the dose of your calcium channel blocker or change your cimetidine to a different medicine.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
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