Sildenafil and Tadalafil Together: What the Approved Labels Say

Each medicine improved erections more than a placebo in its own studies. In a 12-week trial of 329 men with erection difficulties, 69% of attempts at sex were successful with sildenafil in the last four weeks.

That compares with 22% on placebo. The figure counts attempts, not men, and doses could be raised during the trial.

In five 12-week trials of 1,112 men with erection difficulties, 81% of men taking tadalafil as needed reported improved erections. That compares with 35% on placebo.

In a 12-week trial of 268 men, 84.5% of those taking tadalafil daily reported improved erections, compared with 28.3% on placebo. That was a secondary measure, based on what the men reported, and Daily Boost wasn't the study product.

These are separate studies with different measures, so each figure describes one medicine on its own, not a comparison of the two or the combination. Each tested an oral medicine, not a compounded pairing or your prescribed strength. Study doses aren't instructions for use, and results vary.

Not on your own. Each approved label says the safety and effectiveness of combining it with other PDE5 inhibitors or other erectile dysfunction treatments haven't been studied. The sildenafil label adds that such combinations may lower blood pressure further and aren't recommended, and the tadalafil label asks prescribers to tell patients not to take it with other PDE5 inhibitors.

A pairing like Double Powered is compounded and used off-label, against that label guidance. Whether it's right for you is your provider's call, based on your history. Never add another erection medicine yourself.

A licensed pharmacy mixes your medicine for you, to the prescription your provider writes. Compounded medicines aren't FDA-approved, and the FDA doesn't review their safety, effectiveness or quality before they're marketed.

A compounded pairing isn't a generic of a brand-name pill, because there's no approved two-medicine product for it to copy. It has no FDA-approved prescribing information of its own, so follow your provider's instructions and the directions that come with your prescription.

Nitrates, such as nitroglycerin for chest pain, aren't taken with sildenafil or tadalafil in any form, whether regularly or only now and then. Both approved labels list them as a contraindication, because these medicines can make the drop in blood pressure that nitrates cause stronger. The same goes for guanylate cyclase stimulators such as riociguat.

Tell your provider about alpha-blockers and other blood pressure medicines too, since together they can lower blood pressure further, sometimes enough to cause dizziness or fainting. Also mention any version of either medicine prescribed for high blood pressure in the lungs.

The labels say these medicines aren't for anyone taking a nitrate or a guanylate cyclase stimulator, or anyone with a known allergy to sildenafil or tadalafil. Your provider reviews your history first.

The sildenafil label adds that erection treatments generally shouldn't be used by men whose heart health makes sexual activity inadvisable. It also notes that controlled data don't exist for some groups, including men with a recent heart attack or stroke, or with unstable angina.

Common side effects listed on the sildenafil label include headache, flushing, indigestion, abnormal vision, nasal congestion, back pain, muscle aches, nausea, dizziness and rash. The tadalafil label lists headache, indigestion, back pain, muscle aches, nasal congestion, flushing and pain in a limb.

Stop taking them and get medical help right away for a sudden loss of vision in one or both eyes. It can be a sign of a rare condition called NAION that can reduce vision, sometimes permanently. Do the same for a sudden decrease or loss of hearing, which may come with ringing in the ears or dizziness.

Neither medicine protects against sexually transmitted diseases.

Get medical help right away. The approved sildenafil labeling says to seek immediate medical help for an erection that lasts longer than four hours. If priapism (a painful erection lasting more than six hours) isn't treated right away, it could cause lasting harm to penile tissue and permanent loss of potency.

Your provider picks one medicine or two based on your health history, and the pairing isn't offered as the stronger option. Because combining them hasn't been studied, neither label supports calling the pairing stronger, faster or longer-lasting than either medicine alone.

Yes. Both are prescription medicines, and a licensed provider reviews your health history before prescribing. The FDA also warns about sexual enhancement products sold as supplements that turn out to contain hidden drug ingredients, which matters most if you take a nitrate.