If your erectile dysfunction (ED) drugs don’t have you rising to the occasion, it doesn’t necessarily mean you’re out of luck. Many men who fail to respond to ED meds are taking them incorrectly, finds new research from Spain.

In the study, 69 percent of guys who reported that their penis problems persisted even after taking PDE5 inhibitors—first-line ED drugs such as Viagra, Cialis, and Levitra—were making some errors when downing the pills.

The researchers offered these patients a “re-education” program to help them better understand how they should use the meds. Of the guys that accepted, 77 percent then responded favorably to the ED drugs.

The problem: Many men aren’t given enough information on how to use the drug when they’re prescribed it. That’s especially true if they only bring up their erection issues as a last-minute concern when their primary care visit is just wrapping up, says Jacob Rajfer, M.D., professor of urology at the David Geffen School of Medicine at UCLA.

“A lot of men go out without being properly educated,” Dr. Rajfer says.

See how men commonly misuse ED drugs, and learn from their mistakes:

DON’T EXPECT A MIRACLE

Most guys know that these meds don’t magically give them an erection. Still, 3 percent of study participants reported they weren’t getting enough sexual stimulation when trying them out.

If you’re not aroused, you might as well have just popped a placebo. That’s because of how the drug works in your body.

When you get sexually excited, your brain sends a signal via the nerves down to your penis. This releases a chemical into the muscle of the penis, which then sparks the production of another chemical—the one your ED meds work on to give you a boner. If you’re not aroused, that second chemical wouldn’t form in the first place.

“We tell men not to take the drug and expect miracles happening without doing some work—foreplay, things like that,” says Dr. Rajfer. “It will not work unless you have some form of sexual stimulation, be it touch, taste, smell, whatever that is.”

 TAKE MORE THAN THE BARE MINIMUM

Unless you’ve reached the max dosage, don’t assume your meds aren’t going to work for you—an error shared by 31 percent of the study participants.
It might be tempting to start at the lowest dose—who wants to take more medication than they need?—but the reality is, it might not be enough to treat the problem. And that can leave guys frustrated.

“For the majority of men who come in really complaining about ED, if it’s going to work, it’s going to work at the higher dose,” says Dr. Rajfer.

Exception: If you have other health conditions, like hypertension, diabetes, or high cholesterol, your doctor will probably start you on a lower dose to make sure you can tolerate the medication, he says. Otherwise, ask your doc if your prescription is for the max.

 DON’T EAT BEFORE POPPING THE PILL

If you’ve just had a big dinner, a romp in the bedroom right after might not be in the cards. Over 20 percent of men in the study made the mistake of taking Viagra or Levitra too soon after eating.
That’s a major problem. Those two drugs work best on an empty stomach, so you need to wait at least 2 to 3 hours after a full meal to take them, says Dr. Rajfer.

“If you have food in your stomach with those drugs, only half the drug gets absorbed,” he explains. “So if someone whose penis requires 100 milligrams (mg) takes that 100 mg with food in his stomach, he is really only getting a 50 mg dose.”

Just remember that’s only true for Viagra or Levitra. Cialis, on the other hand, doesn’t carry any restriction in regards to when you should chow down.

 WAIT A LITTLE WHILE TO HAVE SEX

We know you’re eager, but it really does pay to wait. One in six guys in the study screwed up by initiating sex too soon after popping the pill.

If you’ve got a script for Viagra or Levitra, you need to wait at least 1 hour before getting busy. That’s when the drug reaches its peak level in your system, says Dr. Rajfer. Cialis reaches its highest level between 2 to 3 hours after you swallow it.

Now, that’s not to say that there won’t be enough of the drug in your system to help you get an erection 15 minutes after you take it—or even 12 hours later. But when you’re first testing to see if you will respond to the drug, it makes the most sense to try it when it’s at its peak level.

“Once you know it works, then you can play around with the time,” Dr. Rajfer says.

 TEST IT OUT SEVERAL TIMES

If you don’t pop wood during the first test, it doesn’t mean you’re sunk. Still, 33 percent of men in the study reported not trying their meds on at least six different occasions, which is commonly considered a standard recommendation.
That number is actually a holdover from how the drug was originally recommended back in the 1990s, says Dr. Rajfer. Back then, the line of thinking was to begin the medication at the lowest dose and try it twice. If that didn’t work, you’d bump up to a higher dose and give that two shots. And so on, until you reached the max.

Now, most men aren’t usually started on the lowest dose, so you don’t necessarily need to try it six different times. But it’s still a good idea to try each dose at least twice before believing it won’t work for you, says Dr. Rajfer. That’s to make sure that you’re not getting messed up by any other factors, like lack of sexual stimulation or a full stomach.

TRY MORE THAN ONE MED

If you’ve failed to respond to one drug, you might be tempted to throw in the towel. That was the most common mistake made by men in the study; 40 percent didn’t try another kind after the first was unsuccessful.
While the study points out there’s no conclusive evidence that a different kind of drug can improve your erection, it doesn’t hurt to try.

“Every patient will respond differently between drugs,” says Dr. Rajfer.

It’s reasonable to assume a change will benefit some guys, and it’s important to exhaust all PDE5 inhibitor options before moving on to the next line of treatment. Often times, that’s a more invasive drug you can try called alprostadil, which is given either through an injection in your penis or a suppository in your penis’s opening.