Brief Answer:
Please refer to the detailed answer below

Detailed Answer:
Hello Sir

After going through the medical query raised by you I would like to tell you that Perindopril has no know interaction with sildenafil.

But Bisoprolol do has interaction with hepatic clearance of sildenafil make its action more pronounced.

So its highly advisable that you should personally consult your doctor for opinion and proper dose of sildenafil if really needed.

I hope this information will answer your query.

Kind Regards
Dr Bhanu partap

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