If a man faces only minor difficulties with erection than the approved dosage of 20 mg should be more than enough. Under normal circumstances, when a man is sexually stimulated, the penis fills up with blood. Please note that it is always possible to split tablet by 2 and get half of a suggested dosage. For severe cases, the dosage can be raised to 40 mg per day under the supervision of your doctor. If you have any sort of questions regarding where and ways to use viagra online, you can contact us at our site.