Avanafil Stendra. Its effects often last for 4 to 5 hours. They include dutasteride Avodart, Jalyn and finasteride Propecia, Proscar. These include itraconazole Sporanox, Tolsura , ketoconazole Extina, Ketozole, others and ritonavir Norvir. Stop taking VIAGRA and call your healthcare provider right away if you have any sudden vision loss sudden hearing decrease or hearing loss.Pfizer, the company that makes brand-name Viagra, has found dangerous substances like printer ink, amphetamines (“speed”), and metronidazole (an antibiotic) in these counterfeit Viagra pills. Luckily, there are both over-the-counter “natural” alternatives to Viagra you can try, and ways to get real, prescription medication without . There are several medications and treatments used to treat erectile dysfunction (ED, impotency), including Viagra (sildenafil), testosterone replacement therapy, penile self . Key takeaways: Muse, Caverject, and Trimix can be good substitutes for Viagra (sildenafil). But they require insertion or injection into the penis. There’s some evidence that L-arginine might help with ED as an oral supplement. But it may not be safe for everyone. There’s not much evidence that trazodone, ginseng, or yohimbine help .