Educational only. We do not sell medicine. Never combine an ED pill with a nitrate. Emergencies: call 911 in the United States.

MensRxGuide Sexual health and ED medication guide

Medication guide

Vardenafil (Levitra, Staxyn) and avanafil (Stendra)

These are the other two PDE5 inhibitors approved in the United States for erectile dysfunction. They do not work when sexual stimulation is missing, and they are contraindicated with nitrates and with guanylate cyclase stimulators. They earn a separate page because each has a labeling detail the sildenafil-versus-tadalafil comparison does not capture: vardenafil and the QT interval, the Staxyn tablet that dissolves on the tongue, and avanafil’s 15-minute dosing language.

Vardenafil film-coated tablets (Levitra)

For most patients the labeled starting dose is 10 mg, taken about 60 minutes before sexual activity, up to once a day. The dose may be increased to 20 mg or decreased to 5 mg. Tablets also exist at 2.5 mg. The tablet may be taken with or without food. A starting dose of 5 mg is what the label says to consider for adults 65 and older, for moderate hepatic impairment, and for men already stable on an alpha-blocker.

Strong CYP3A4 inhibitors force lower caps. With cobicistat, the label’s limit is no more than 2.5 mg in a 72-hour period. Other inhibitors have their own maxima. This is a pharmacist question, not a pill-splitting project.

The QT caution

Vardenafil can prolong the QT interval. People with congenital long QT syndrome, and people taking class Ia antiarrhythmics (such as quinidine or procainamide) or class III antiarrhythmics (such as amiodarone or sotalol), are told to avoid it. That single precaution is a reason a prescriber may choose a different PDE5 inhibitor even when the erection window would otherwise look similar to sildenafil. Bring a current list of heart-rhythm medicines to the visit.

Staxyn is not “Levitra that melts”

Staxyn is an orally disintegrating vardenafil tablet supplied at 10 mg. It is placed on the tongue to dissolve, without water. It is not approved as a higher dose, and labeling has long warned that it is not interchangeable, milligram for milligram, with the film-coated tablet, because the dissolving tablet produces higher exposure. Do not substitute one for the other on your own, and do not take it with a sip of liquid that you then swallow as if it were an ordinary tablet. If a generic orodispersible product is dispensed, read that product’s leaflet. The brand-specific instructions are the ones that match the bottle in your hand.

Avanafil (Stendra)

Avanafil’s labeled starting dose is 100 mg, taken as early as about 15 minutes before sexual activity, no more than once a day. If that is more than you tolerate, the dose may be decreased to 50 mg, timed at about 30 minutes. If 100 mg is not enough and side effects allow, it may be increased to 200 mg, still as early as about 15 minutes. The lowest dose that works is the one the label prefers. It may be taken with or without food.

Strong CYP3A4 inhibitors are a hard stop on this label, not a dose reduction. Ketoconazole, ritonavir, atazanavir, clarithromycin, itraconazole, and related strong inhibitors mean do not use avanafil. Moderate inhibitors, including erythromycin, fluconazole, diltiazem, and verapamil, cap the dose at 50 mg in 24 hours. Men stable on an alpha-blocker start at 50 mg. More than about 3 units of alcohol raises the chance of a blood-pressure drop; the Stendra label calls that out directly.

Common reactions at or above 2 percent in trials include headache, flushing, nasal congestion, nasopharyngitis, and back pain. The 4-hour erection rule, sudden vision loss, and sudden hearing loss are the same emergencies as for the rest of the class.

Diabetes and the “best pill” claim

Erectile dysfunction is common in diabetes because high blood sugar injures both the small vessels and the nerves that start the nitric oxide signal. A PDE5 inhibitor can only amplify a signal that the nerves and vessels can still produce, so response rates are often lower than in men without diabetes. No brand in this pair is a specific antidote for diabetic ED. What does change the odds is glucose control, blood pressure, lipids, smoking, and treatment of sleep apnea, alongside a properly prescribed PDE5 inhibitor if the heart and the medicine list allow it.

Avanafil’s faster labeled onset is a scheduling advantage. It does not bypass neuropathy. If pills fail, a urologist can discuss devices, alprostadil, and other options that do not depend on the same nerve signal. Those are outlined under lifestyle changes and alternatives.

Cost

Generic vardenafil exists but is stocked less consistently than generic sildenafil. Avanafil has had less generic competition, so the cash price is often higher. A higher price does not make a drug safer. A suspiciously low price from a seller that does not require a prescription is a different product than the one described here.

Compare all four in the matrix.

Sources