Since alcohol may increase some of the side effects of this drug, it should be avoided. Inform your doctor if you take any prescription or non-prescription drugs that tend to make you drowsy, since this drug may intensify that effect. It is also important to tell your doctor if you take any drugs for erectile dysfunction or enhancement, since these also affect the blood flow in the body. Some drugs taken together may cause increased side effects, but being taken together may be the only option for the best treatment. Therefore, it is important to make your doctor aware of all drugs you are taking so they can monitor and modify the dosages.