Drug studies have shown that tadalafil tablets can improve erectile function in men within 36 hours of taking them on demand, but the exact duration of action varies from person to person and cannot be determined. As a kind of male erectile dysfunction treatment drugs, tadalafil tablets of the drug description suggests that this product can improve erectile function within 36 hours after the use of drugs, but the specific duration of action may be different depending on the individual’s physical condition, the dosage of the drug, the severity of the disease and other factors. Therefore, it is not possible to give a precise answer to the question “how long can it be prolonged”. Adverse effects such as headache, dyspepsia, back pain, myalgia, etc. may also occur during the course of the medication. It should also be noted that tadalafil tablets are contraindicated in people who are allergic to them or are using nitrates such as isosorbide mononitrate. It is contraindicated in patients who have had a myocardial infarction within 90 days, unstable angina or who have had angina during sexual intercourse, uncontrolled arrhythmia or hypertension. Therefore, if there is a real need for the use of this drug, it must be used under the guidance of a doctor, do not blindly take the drug or increase or decrease the dosage of the drug, in order to avoid adverse consequences.