A penis pump, formally called a vacuum erection device (VED), draws blood into the penis using suction to produce an erection. It’s one of the most established, non-drug treatments for erectile dysfunction, with success rates exceeding 80% in clinical studies. Beyond ED, these devices are also used for penile rehabilitation after prostate surgery and as a conservative treatment for Peyronie’s disease.
How a Penis Pump Works
The device consists of a plastic cylinder that fits over the penis, a pump (manual or battery-powered) that removes air from the cylinder, and a constriction ring that slides onto the base of the penis afterward. When air is pumped out, the resulting vacuum pulls blood into the erectile tissue. Color Doppler ultrasound studies show that vacuum exposure increases blood flow velocity through the central arteries of the penis, and the cross-sectional area of the erectile chambers roughly doubles during use.
Once the penis is erect, you slide the constriction ring off the cylinder and onto the base of the penis. This ring acts like a tourniquet, trapping blood so the erection holds long enough for intercourse. The ring should not stay on for more than 30 minutes to avoid tissue damage.
Treating Erectile Dysfunction
The American Urological Association lists vacuum devices as a recommended treatment option for ED and notes that men don’t need to exhaust other treatments first. Any type of ED treatment is considered a valid starting choice, whether that’s oral medication, a vacuum device, or something else. For men who don’t respond to oral ED medications, a vacuum device can serve as a “rescue” option. European and British guidelines similarly position vacuum devices as a first-line treatment when oral medications fail.
When used in combination with oral ED medication, success rates climb even higher. One study found that daily vacuum therapy paired with medication taken three times weekly produced a 90% success rate at one year, compared to 60% in men using medication alone.
Recovery After Prostate Surgery
One of the most important medical uses for a penis pump is penile rehabilitation after radical prostatectomy (prostate removal surgery). The surgery can damage nerves that control erections, and without regular blood flow to the erectile tissue, the penis can lose length and the tissue can atrophy. Research shows this nerve-related muscle loss is most pronounced between 4 and 8 months after surgery.
Starting vacuum therapy early, typically within one week to one month after surgery (once the catheter is removed), helps maintain the health of penile tissue. In one study, 80% of men who began using a vacuum device early after surgery were able to have intercourse successfully. Even without a constriction ring, using the pump for rehabilitation purposes resulted in a 60% improvement in the return of natural erections over time. About 30% of men using a vacuum device alongside oral medication reported spontaneous erections returning on their own.
Reducing Curvature in Peyronie’s Disease
Peyronie’s disease causes scar tissue to form inside the penis, creating a noticeable curve that can make intercourse painful or difficult. Vacuum therapy offers a non-invasive alternative to injections or surgery. In a study of 53 men with Peyronie’s disease, every single patient who used a vacuum device (10 minutes, twice daily) saw improvement in their curvature, with an average reduction of 23 degrees, a 44% improvement. By comparison, untreated men improved by only 3.6 degrees on average, and most saw no change at all. Men with more severe curvature tended to see the greatest benefit, and age didn’t affect results.
Will It Permanently Increase Size?
This is one of the most common questions about penis pumps, and the answer requires some nuance. A vacuum device temporarily increases both length and girth while it’s in use, simply by engorging the tissue with blood. That effect fades once the device is removed and blood flow returns to normal.
Penile traction devices (a related but different category that applies gentle stretching force over hours) have shown modest permanent gains in some research. One preliminary study of 23 men found that average flaccid length increased from about 8.8 cm to 10.5 cm over three months of use, and stretched length increased from 11.5 cm to 13.2 cm. Girth, however, did not change significantly. These results involved a traction device, not a standard vacuum pump, so they shouldn’t be assumed to apply to typical ED pumps used for short sessions.
Manual vs. Battery-Powered Pumps
Manual pumps use a hand-operated lever or plunger to create suction. They come in one-handed and two-handed models, let you control the pace precisely, and tend to produce an erection more quickly. Battery-powered pumps automate the suction process, making them a better fit if you have arthritis, limited hand strength, or reduced dexterity. They also build pressure more gradually, which some men prefer. Battery models typically cost more, but the clinical outcomes are comparable between the two types.
Risks and Who Should Avoid Them
Side effects are generally mild. The most common issue is petechiae, tiny red or purple dots on the skin caused by broken capillaries near the surface. Bruising and, in rare cases, a hematoma (a pocket of trapped blood under the skin) can also occur, particularly with excessive suction or prolonged use of the constriction ring.
The FDA advises against using a vacuum pump if you have sickle cell disease, a history of prolonged erections (priapism), or if you take high doses of aspirin or other blood thinners. These conditions increase the risk of bruising and bleeding complications. The erection produced by a vacuum device also feels somewhat different from a natural one. The penis may feel cooler to the touch since the trapped blood isn’t circulating, and the base (below the constriction ring) won’t be fully rigid. Most couples adapt to these differences without difficulty.