Cialis is the trade name and generic name for tadalafil tablets, which can improve erectile dysfunction with regular long-term use of 5 mg of this product. Tadalafil belongs to the group of phosphodiesterase type 5 inhibitors and improves erectile ability. This product can be taken as needed before the onset of sexual intercourse or in low doses for long periods of time. Long-term administration of this product 5mg is effective in enhancing erectile function and it is recommended to review the erectile function after 3 months of administration. Side effects that often occur after the use of tadalafil include flushing, dizziness, headache, visual abnormalities, limb pain, back pain, etc. It is contraindicated for those who are allergic to the drug, and it should not be used in combination with nitrate drugs. It is recommended to take medication under the guidance of a physician, and should not be used blindly.