Tadalafil should refer to tadalafil, the general antihypertensive drugs with tadalafil is possible, but with alpha receptor antagonists such as uradil, phentolamine, terazosin, etc., will make the risk of hypotension increased, so that the combination of drugs is not recommended. Tadalafil is a selective inhibitor of phosphodiesterase 5, the specific enzyme that breaks down cyclic guanosine monophosphate, and is used clinically for the treatment of erectile dysfunction in men. Its main effect is to inhibit the decomposition of cyclic guanosine phosphate and enhance the vasodilatory effect of nitric oxide. Because of the similarity of the principle of action with nitrate drugs, it is strictly prohibited to take with nitrate drugs at the same time. In addition, tadalafil is also prohibited for those who are allergic to the drug components, patients with unstable angina pectoris, patients who have had myocardial infarction within 3 months, patients who have had severe heart failure within 6 months, intractable cardiac arrhythmia and low blood pressure and so on. When using tadalafil, patients must use the drug under the guidance of a specialist, strictly grasp the contraindications to avoid adverse consequences.