How the interaction occurs:
When these two medicines are taken together, your body may not process sildenafil properly.
What might happen:
Your blood levels of sildenafil may increase and cause harmful effects.
What you should do about this interaction:
Contact your healthcare professional (e.g. doctor or pharmacist) if you experience a painful or prolonged erection. Your doctor may want to change your dose of sildenafil.Your healthcare professionals 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.Reference:1.Viagra (sildenafil) US prescribing information. Pfizer Inc. March, 1998.