Often, these are prescribed for chest pain called angina. These small differences affect the way each medication works, such as how quickly it takes effect and wears off, and the possible side effects. Since alcohol decreases blood flow to the penis, it limits the drug’s effectiveness i. Taking sildenafil citrate with other drugs like cocaine Mixing ED drugs with hard drugs is inherently dangerous. The body takes longer to absorb it after a high-fat meal or alcohol. Often they sell drugs with missing active ingredients or in smaller amounts.The safest way to get a prescription for Viagra is from your doctor. You can even do this over a telehealth call (on the phone or computer) in many cases, although for your first . Can you get Viagra without a prescription? You cannot legally get Viagra in the United States and most other countries without a prescription. The United Kingdom is one . Other options. There are several options to treat erectile dysfunction aside from oral medications like Cialis, including: erectile dysfunction pump, which can be a penis or .