No. You shouldn't use this medicine if you take any of these forms of nitroglycerin or any other nitrates:

• Isosorbide mononitrate (brand names: Ismo, Monoket, Imdur)
• Isosorbide dinitrate (brand names: Isordil, Sorbitrate)
• Sublingual nitroglycerin tablets or spray (brand names: Nitrostat, Nitrolingual Spray)
• Transdermal nitroglycerin patches or paste (brand names: Minitran, Nitro-Dur, Transderm-Nitro)

You also shouldn't take sildenafil if you are taking other medicines for erectile dysfunction.

If you use sildenafil and get chest pains, be sure to tell the paramedics, nurses or doctors at the hospital that you use it and how long ago it was that you last took a tablet.