How the interaction occurs:
The cause of the interaction is unknown. Beta-blockers may increase the chance that you will have a sudden decrease in your blood pressure when starting your prazosin.
What might happen:
You may experience a sudden decrease in your blood pressure when starting prazosin, if you are already taking a beta-blocker. This problem may be worsened if you are also taking a water pill (e.g. a diuretic) or are on a low salt diet.
What you should do about this interaction:
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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