Cialis tadalafil : This ED medication works with the same principle as Viagra, but lasts up to 36 hours. This increase in blood flow results in a firmer, longer-lasting erection. Privacy: Confirm that your personal data and payment details are confidential. Your health information should remain between your provider and yourself. Most erectile dysfunction medications belong to the drug class known as PDE5 inhibitors , which help relax the muscles and increase blood flow to allow for a full erection.Reducing long-term drug costs. Financial assistance. Next steps. Viagra (sildenafil) is a brand-name oral tablet prescribed for erectile dysfunction. The cost of the drug with and . as low as. $ View other PDE5 Inhibitors. Sildenafil (Viagra, Revatio) is a moderately priced drug used to treat erection problems in men. It is also used to treat pulmonary arterial hypertension, a serious heart and lung condition. This drug is more popular than comparable drugs. It is available in generic and brand versions. Cost: Consultation prices vary based on the prescriber; $5 generic prescriptions. Medical Consultation Required: Yes. Medications Prescribed: Viagra, Cialis, sildenafil, tadalafil. Generic offered: Yes. Why We Chose It.