Guanethidine; Guanadrel/Phenothiazines Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

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, the amount of blood pressure medicine used by your body may be decreased.

What might happen:

The beneficial effects of your blood pressure medicine may be decreased. These decreased effects may be seen for several days after stopping your phenothiazine.

What you should do about this interaction:

You should check your blood pressure regularly. Tell your doctor if there is a change in your blood pressure, since he may need to change the dose of your medicine depending on your blood pressure. You should also tell your doctor if you have any chest pain or shortness of breath, or if you have any dizziness, headache, or blurred vision.Make sure that your doctor knows all of the medicines that you are taking.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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CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.