However, others work on a cash-pay basis and don’t partner with insurance companies. Consideration should be given to the following: Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor. Patients should be advised to contact the prescribing physician if other anti-hypertensive drugs or new medications that may interact with LEVITRA are prescribed by another healthcare provider. You’ll also need to fill out a medical questionnaire with answers about your medical history, current medications, and lifestyle habits. Online telehealth services like Lemonaid offer you both safety and convenience. Popular ED medications found online include: Viagra sildenafil : As the first FDA-approved PDE5 inhibitor for ED, sildenafil is taken 30 minutes to four hours before sexual intercourse to help achieve and maintain an erection. These include chest pain and tightness, shortness of breath, extreme lightheadedness, and swelling in the hands and feet.Vardenafil, sold under the brand name Levitra among others, is a medication that is used for treating erectile dysfunction. It is a PDE5 inhibitor. It is taken by mouth. Medical use. Vardenafil’s indications and. How Vardenafil works. Vardenafil is a phosphodiesterase-5 enzyme (PDE-5) works by blocking PDE-5, a protein in your body that normally prevents an erection from it blocks PDE-5, vardenafil helps an erection occur by allowing certain muscles in the penis to relax and the penis to fill with blood. Hearing loss or ringing in ears. Heart attack—pain or tightness in the chest, shoulders, arms, or jaw, nausea, shortness of breath, cold or clammy skin, feeling faint or lightheaded. Low blood pressure—dizziness, feeling faint or lightheaded, .