Avan is a drug, commonly known as Viagra.
Viagra (sildenafil citrate tablets) is the world's first oral PDE5 inhibitor (phosphodiesterase type 5 inhibitor), which is used to treat male erectile dysfunction (also known as impotence or ed), which promotes the revolutionary progress of ed treatment and effectively improves the erectile hardness of penis.
composition
The main component of this product and its chemical name are: 1-[4- ethoxy -3- (6,7- dihydro-1- methyl -7- oxo-3-propyl-1 hydro-pyrazolo [4,3d] pyrimidine -5- yl.
Chemical structural formula:
Molecular formula: C22H30N6O4S C6H8O7.
Molecular weight: 666.70
Please use it under the doctor's diagnosis prescription and take it accurately according to the dose told by the medical staff. The medical staff will tell you the dosage and time. If necessary, the medical staff can adjust the dose. The following patient information is for reference only (US Food and Drug Administration, Viagra? Instructions, patient information; Pfizer China, instructions for Viagra):
Take it about before sexual activity 1 hour. If necessary, it can also be taken within 30 minutes to 4 hours before sexual activity. Viagra can be taken before or after meals. If you take it after a high-fat meal (such as hamburgers or French fries), it may take a little longer for the drug to take effect. Do not take Viagra more than 1 time a day. If you accidentally take too much Viagra, contact your doctor immediately or go to the nearest hospital emergency room.
For most patients, the recommended dose is 50 mg, which is taken on demand about 1 hour before sexual activity; But you can take it at any time within 0.5-4 hours before sexual activity. According to the efficacy and tolerance, the dose can be increased to 100 mg (the maximum recommended dose) or decreased to 25 mg. Take 1 time at most every day. The recommended dose of sildenafil has no effect without sexual stimulation.
The following factors are related to the increase of plasma sildenafil level (AUC): age over 65 (increased by 40%), liver damage (such as liver cirrhosis, increased by 80%), severe renal damage (creatinine clearance rate [30ml/min, increased by 100%), taking powerful cytochrome P4503A4 inhibitors [ketoconazole, itraconazole] Because higher plasma levels may increase both the efficacy and the incidence of adverse events, the initial dose of these patients is 25 mg.