Penis pumps, or vacuum erection devices (VED), can increase blood flow to your penis to help you achieve or maintain an erection. But they can’t permanently lengthen your penis.

Penis pumps use a vacuum to draw blood into the penis. They’re a common noninvasive treatment option for people living with erectile dysfunction (ED) because they may help you achieve or maintain an erection.

This article discusses the efficacy of penis pumps and the science behind their use.

Penis pumps can help people to achieve and maintain erections.

Research suggests they may help people living with ED achieve an erection in up to 90% of cases. Other research highlights that for people with ED and their partners, up to 77% are happy with the outcomes of penis pump use.

If you have ED, penis pumps are generally less expensive and safer than other options when used correctly. You can also use them alongside ED medication, like sildenafil (Viagra).

Small studies also show that, in combination with medications, penis pumps can help to preserve penis function and reduce shrinkage following prostate cancer surgery.

A penis pump works by using suction to draw blood into the penis.

The blood fills the blood vessels in your penis, causing them to swell so your penis gets — temporarily — bigger and harder.

A constriction ring — better known as a cock ring — is usually placed around the base of the penis to help keep the blood in the penis and maintain the erection.

Penis pumps, or VEDs, are generally safe, but they may not be right for people with certain medical conditions.

According to the Food and Drug Administration (FDA), using a penis pump or other external rigidity device could aggravate penile conditions, such as priapism.

Too much air pressure in the cylinder can also cause mild bleeding under the skin’s surface. For this reason, penis pumps may not be right for you if you:

A cock ring that’s too tight or left on too long could cause your penis to become bruised, numb, and cold.

The duration of an erection can vary when using penis pumps. Many product manufacturers suggest that around 30 minutes is a typical outcome. Factors like your arousal level and overall health status can also influence how long the effects last.

For those with ED, penis pumps alone are unlikely to result in a full erection. In this instance, the use of a constriction device is necessary.

Cock rings can help to extend erection times. However, it’s unsafe to use them for more than 30 minutes. Extended use of constrictive devices on the penis can lead to swelling and potentially severe injury.

There’s no set limit to daily penis pump uses. Experience, comfort, and necessity will often dictate usage. Most people can use it safely multiple times a day if needed, as long as they use it correctly.

If a penis pump is causing pain or discomfort, it’s best to stop using it immediately. If pain persists, seek medical assistance.

Maintaining a balanced lifestyle can go a long way when it comes to improving penile function and getting stronger erections. This may include:

Certain medications can also affect your sex drive and cause erection problems, such as antidepressants and blood pressure medications. Speak with a doctor if you think your medication may be the issue.

There’s no reliably safe way to increase your penis size without surgery. However, it’s important to remember that penis size doesn’t matter in terms of function.

If you feel anxious about the size of your penis, consider speaking with a therapist. They may help you identify, understand, and develop coping strategies to work through feelings of anxiety.

Some VEDs may have more features than others, but the basic function is the same:

  1. Place the tube over your penis.
  2. Pump out the air, using the hand pump or electric pump attached to the tube, creating a vacuum effect.
  3. Once you’re erect, remove the pump.
  4. You can place a constriction ring around the base of your penis to help you maintain your erection.

It’s important to carefully follow the instructions on the packaging label to minimize your risk of injury.

Penis pumps can increase blood flow to the penis to help you get or maintain an erection. But they don’t permanently increase the girth or length of your penis.

How long it takes for a penis pump to achieve an erection can vary. Your erection from a penis pump can typically last for about 30 minutes but may depend on other factors.

Some research suggests that a penis pump may be slightly more effective than Viagra, and that participants reported higher satisfaction rates when using penis pumps.

That said, you can use penis pumps with ED medication like Viagra, which may be more effective than either treatment alone.

Penis pumps can effectively help you reach and maintain an erection if you’re living with ED. However, they’re not a penis enlargement device and any change in penis size will be temporary.

Adrienne Santos-Longhurst is a freelance writer and author who has written extensively on all things health and lifestyle for more than a decade. When she’s not holed up in her writing shed researching an article or off interviewing health professionals, she can be found frolicking around her beach town with husband and dogs in tow or splashing about the lake trying to master the stand-up paddle board.