Suhagra 100 mg with a doctor before taking it include: Anyone with heart or cardiovascular disease, particularly if sexual activity may be unsafe. People taking nitrate medicines such as nitroglycerin or isosorbide — sildenafil should not be combined with these medicines. People taking Suhagra 100 mg  or blood-pressure medicines, because sildenafil can further lower blood pressure. People with significant kidney or liver problems, who may require a lower dose. Anyone taking other prescription medicines that could interact with sildenafil. People who have previously experienced sudden vision or hearing loss associated with sildenafil or similar medicines. If Suhagra 100 mg contains sildenafil 100 mg, 100 mg is the maximum recommended sildenafil dose for ED and should generally be taken no more than once daily.