Brief Answer:
The drugs interact, both reduce blood pressure.

Detailed Answer:
Hello,
Sildanefil ( Viagra) can actually add your b.p lowering effect along with your lisinopril, so if you feel sudden dizziness, giddiness, flushing, flashes of lights, increased heart rate please consult your doctor immediately, when ever you are taking two drugs it's always better that you inform your consultant , so he tells you if there are any intercations between the two, your consultant might either reduce the dose or any other alternative. Hope I could help you.
Thank you.

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Brief Answer:
Other tablets of same class also cause hypotension

Detailed Answer:
Hello,
Thanks for getting back, there are other drugs of the same group such as Vardenafil and tadalafil along with sildenafil, and all these have similar kind of actions and similar side effects.
These two other drugs also have B.p lowering effects. Please kindly consult your doctor, as he can only explain;
1) According to your condition and status wether tablet lisinopril can be changed to another alternative .
2) otherwise , doctor will tell you what advice to follow in case you are using both together, which is not advisable .
3) please be aware of symptoms of low blood pressure as I mentioned above.
4) Consulting your doctor is the best option.
Hope I could help you.
Thank you.

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