Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, your sympathomimetic may decrease the ability of guanethidine to lower your blood pressure.
What might happen:
Your blood pressure may increase.
What you should do about this interaction:
If your doctor prescribes these two medicines together, you may need to check your blood pressure more often. It may be necessary to change you to a different blood pressure medicine.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 stop, start, or change the dosage of any medicine before checking with them first.
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