For many people with hypertension, taking Viagra is safe and effective, but when starting any new prescription, including medications for ED, it is important to discuss it with your doctor or another healthcare professional. They will thoroughly evaluate your health history, current list of medications, and other factors to determine the safest and most appropriate course of treatment for you. Viagra can interact with some classes of heart failure or blood pressure medications like alpha-blockers and nitrates, causing an unsafe drop in blood pressure. If you are taking several medications or are unsure if Viagra is contraindicated given your current medication regimen, seek an explanation from a trusted medical professional.