No, it is not safe to take nitrate medicine (such as a treatment for chest pain) and Viagra (sildenafil) together. This is because combining these types of medication can potentially lead to a dangerous fall in your blood pressure, causing fatal hypotension and subsequent side effects. You should always consult a doctor, pharmacist or healthcare provider if you are taking nitrate medications prior to taking Viagra (sildenafil) or any other erectile dysfunction medication.