There are many side effects of Serodosin capsules that can involve multiple systems throughout the body, common side effects include dry mouth, dizziness, headache, diarrhea, rash, constipation, nosebleed, urinary incontinence, stomach upset, ejaculation disorders, bradycardia and erectile dysfunction, in addition to insomnia, gastritis, somnolence, atrial fibrillation, elevated creatinine in the blood, increased bilirubin, and leukopenia. The drug relaxes smooth muscle and can be used in benign prostatic hyperplasia. The drug should be administered after meals to minimize the occurrence of side effects. Caution should be exercised by patients who drive vehicles and operate machinery when using the drug because it can cause side effects such as dizziness. The drug interacts with strong cytochrome P450 3A4 inhibitors such as clarithromycin and ketoconazole, cyclosporine and sildenafil citrate. Contraindicated in the following conditions: severe renal insufficiency with CCr <30mL/min; taking strong cytochrome P450 3A4 inhibitors; hypersensitivity to the drug; children and female patients. Use this drug with caution in patients taking antihypertensive drugs. If you need to use the drug, please follow the doctor's instructions strictly under the guidance of the medication, do not self-medication.