Shenandoah is the trade name and generic name for tadalafil tablets, which has the advantage of treating erectile dysfunction in men and the disadvantage of producing adverse reactions. Tadalafil Tablet is a selective 5-type phosphodiesterase inhibitor, which can increase the level of cyclic guanosine phosphate in the cavernous body of the penis, leading to smooth muscle relaxation and blood flow into the penile tissues, which can treat male erectile dysfunction. However, it is important to note that taking the drug will only cause the penis to become erect through sexual stimulation, and it does not work without sexual stimulation. The disadvantage is that there are adverse reactions, such as headache, dizziness, increased heart rate, etc. The drug is prohibited for those who are allergic to the drug, prohibited for patients taking nitrate drugs, and used with caution in patients with potentially cardiac risk heart disease. There are sexual dysfunction, it is recommended to go to the hospital for examination first, under the guidance of the doctor to use the drug, to avoid their own abuse of drugs.