Head-to-head comparisons of medication uses, side effects, warnings, and more.
Key takeaways
Viagra (sildenafil) and Stendra (avanafil) are both medications used to treat erectile dysfunction (ED), but they have some key differences. Viagra is available as a lower-cost generic, while Stendra is only available as a brand name. Viagra typically takes about 30 minutes to an hour to work and can be taken 30 minutes to 4 hours before sexual activity, whereas Stendra works faster, usually within 15 to 30 minutes. You can take Stendra with or without food, but Viagra works best on an empty stomach. The effects of Viagra can last up to 8 hours, while Stendra's effects last up to 6 hours. Both medications should not be taken more than once a day and have similar side effects, such as headaches and flushing. However, Stendra is noted for causing fewer side effects like indigestion and vision changes compared to Viagra.
Sildenafil (Viagra) is a tablet that's taken by mouth for erectile dysfunction (ED) in adults. It works as a phosphodiesterase-5 (PDE-5) inhibitor to help people get an erection or keep an erection that lasts for sex. You only take a dosage when you need it (usually about an hour, or anywhere from 30 minutes to 4 hours, before sex). Take sildenafil (Viagra) no more than once a day. Otherwise, it can put you at risk of serious side effects, such as vision loss or low blood pressure. Other more common side effects include headache and flushing. Sildenafil (Viagra) is a brand-name and generic medication.