Selected Alpha-1 Blockers/Verapamil
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:
The cause of the interaction is not known. When these two medicines are taken together, the effects of both medicines to lower your blood pressure may increase.
What might happen:
The effects of these medicines to lower blood pressure may be greater than with either drug alone. This may be an advantage. However, additional problems due to excess effects may occur.
What you should do about this interaction:
If you experience weakness or dizziness when you sit up or stand up, contact your doctor.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this drug 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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