Do certain drugs impair Viagra

I have been using Viagra for a couple of years. Recently my Cardiologist has prescribed the following drugs to regulate my blood pressure and now the Viagra is not as effective. Is one of these drugs interfereing with the effectiveness of Viagra?
Cardura, Toprol XL, Mavik, and Teveten HCT

[Kevin Pho, MD]

Hello - thanks for asking your question.

Here is the list of drug interations with Viagra from the Drug Information Handbook:
"Increased effect/toxicity: Cimetidine, erythromycin, ketoconazole, itraconazole, mibefradil, nitroglycerin, protease inhibitors. A reduction in sildenafil's dose is recommended when used with amprenavir, indinavir, or ritonavir (protease inhibitors); no more than 25 mg per dose, no more than 25 mg in 48 hours.

Decreased effect: Rifampin"

There may be no direct interaction with the Viagra, however there are some blood pressure medications that decrease sexual function independent of Viagra (i.e. Toprol XL).  You may want to review your medications with your personal physician.  

Followup with your personal physician is essential.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Thanks,
Kevin, M.D.

[JohnConnor12]

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