How it works, and why it works when drugs do not

A vacuum erection device is three parts: a clear cylinder that fits over the penis, a pump that removes air from it, and an elastic tension ring that transfers from the base of the cylinder onto the base of the penis. Removing air creates negative pressure, negative pressure draws blood into the erectile tissue, and the ring then stops it draining back out. You have an erection, and it lasts as long as the ring is on.

It is also why it is the answer for the group with the fewest options. If you take nitrates for angina, PDE5 inhibitors are absolutely contraindicated — the combination can drop blood pressure catastrophically. That rules out sildenafil, tadalafil, vardenafil, avanafil and every compounded mixture of them, permanently, not just today. A vacuum device has no interaction with anything, because there is nothing to interact.

The evidence, which is better than the marketing budget

What the literature and guidelines say
QuestionAnswer
Does it produce a usable erection?In around 90% of men, across a wide range of underlying causes
Is it in the guidelines?Yes — vacuum erection devices are a recognised option in the AUA erectile dysfunction guideline
Does it work after prostate surgery?Yes, and it is used deliberately in penile rehabilitation protocols to maintain tissue oxygenation while nerves recover
Does it work in diabetes?Yes. Mechanical action is independent of the neuropathy that limits drug response
Do people keep using it?Often not. Long-term continuation is frequently reported under 50%, and dropout is concentrated in the first weeks
Is it safe with nitrates?Yes. No pharmacological interaction exists
See our vacuum device treatment page for the full clinical picture and the rehabilitation protocols.

The gap between a 90% success rate and a sub-50% continuation rate is the whole story of this product, and it is not a mystery. Men stop because it is awkward, not because it fails. Which means the single highest-value thing you can do is get through the first three or four attempts — the learning curve is short and steep, and most of the people who quit never reached the top of it.

Medicare stopped paying for these in 2015

So the practical position is: assume you are paying cash. That is less painful than it sounds, because the cash price is around $130 and there is nothing after it — the reason this was ever an insurance question is that devices used to be billed at several times the retail price.

Commercial insurance
Some plans do cover VEDs, usually with a prescription and often only after documented failure of oral therapy. Worth one phone call before you buy. Our insurance appeals guide covers what to do with a denial.
FSA and HSA
Generally eligible as a medical expense, particularly with a prescription or a letter of medical necessity. This is the most reliable way to make it pre-tax money.
VA benefits
Veterans' coverage operates separately from Medicare and has historically provided devices. Ask your VA provider directly.
Medicare
No. Not since 1 July 2015, and not through Medicare Advantage.

Buying one: the feature that actually matters

Battery or manual?
The Deluxe includes both heads, which is why it is the one worth buying. A battery head is easier if hand strength or dexterity is limited — arthritis, neuropathy, after a stroke. A manual head gives finer control over the rate, which some men prefer, and never needs a battery at the wrong moment.
Ring sizes
The Deluxe ships with seven tension rings in assorted sizes, and getting this right is most of the difference between a device that works and one that does not. Too loose and the erection drains; too tight and it is painful and the 30-minute limit becomes a hard ceiling you will feel.
Cylinder fit
The cylinder needs to seal against the body. A loading cone helps get the ring on. Trimming pubic hair at the base genuinely improves the seal, which is the sort of thing nobody tells you and everybody discovers.
Lubricant
Water-based, generously, at the base of the cylinder. Without it there is no seal, and without a seal there is no vacuum. This is the single most common reason a first attempt fails.

Getting through the first month

Given that most abandonment happens early, this section is the most useful thing on the page. Treat the first few sessions as practice, alone, with no expectation of sex at the end of them.

  1. Practise on your own first, three or four times. The goal is competence with the equipment, not an occasion.
  2. Lubricate the cylinder base generously. Most failed first attempts are seal failures, not device failures.
  3. Pump slowly, in stages. Rapid pumping is uncomfortable and no faster in practice. Pause when you feel pressure build.
  4. Get the ring size right. Start with the middle of the range supplied and adjust. A ring that is too tight is the main source of pain complaints.
  5. Start the thirty-minute clock the moment the ring is on. This is the same limit as any constriction ring and it is not negotiable.
  6. Expect it to feel different. The erection pivots at the base because rigidity stops at the ring, and it may feel cool. That is normal and not a sign anything is wrong.
  7. Involve your partner early. Men who present it as a shared piece of equipment rather than a private embarrassment are markedly more likely to still be using it a year later.
Products

Reviewed individually

Encore sells several different things, and they are not equivalent — some are FDA-approved generics, some are brand-name originals, and some are compounded formulations that have not been through FDA review. Each is reviewed separately, with the retail price of the same molecule shown alongside.

FAQ

Frequently asked questions

Do vacuum pumps really work for ED?
Yes — around 90% of men achieve an erection sufficient for intercourse, which is the highest success rate of any option you can buy without a prescription. The mechanism is mechanical, so it works where drugs fail: after prostate surgery, in advanced diabetic neuropathy, and in severe vascular disease.
Does Medicare cover a vacuum erection device?
No. The ABLE Act of 2014 eliminated Medicare coverage for VEDs, and for dates of service on or after 1 July 2015 the relevant codes are statutorily non-covered. Because the exclusion is statutory, Medicare Advantage plans cannot cover them either. Some commercial plans still do, and FSA and HSA funds are generally eligible.
Do I need a prescription?
No, you can buy one over the counter. A prescription is still worth having — it helps with FSA, HSA and commercial insurance reimbursement, and it means a clinician has sized the device and checked nothing rules it out for you.
How much does the Encore Deluxe cost?
Around $125 to $170 depending on retailer, for both pump heads, the cylinder, seven tension rings and a case. Replacement rings cost a few dollars. There is no subscription and nothing recurring, which is why it is the cheapest effective treatment over any multi-year period.
Is it safe if I take nitrates?
Yes. There is no drug and therefore no interaction. For men on nitrate therapy for angina — where every PDE5 inhibitor is absolutely contraindicated — a vacuum device is one of the few effective options available.
Why do so many men stop using it?
Because it interrupts sex and takes practice, not because it stops working. Continuation is often reported under 50%, and dropout is concentrated in the first few weeks. Practising alone three or four times before using it with a partner is the single biggest predictor of sticking with it.
What is the difference between this and a cheap pump online?
A vacuum limiter. Medical-grade devices cap the negative pressure they can generate; novelty pumps often do not, and over-pumping can rupture blood vessels and cause bruising or lasting injury. It is the only specification worth being fussy about.
How long can the ring stay on?
Thirty minutes, maximum — the same rule as any constriction ring. Remove it immediately for pain, numbness, coldness or colour change, and never fall asleep with one on.
Sources

What this is based on

We link to primary sources — clinical guidelines, regulator publications and peer-reviewed research — wherever possible. Links open on third-party sites we do not control.

  1. [01]American Urological Association. Erectile Dysfunction: AUA Guideline (2018).
  2. [02]National Institute of Diabetes and Digestive and Kidney Diseases. Treatment for Erectile Dysfunction.
  3. [03]Urology Care Foundation. What is Erectile Dysfunction?.
  4. [04]National Library of Medicine. PubMed — search the primary literature.
  5. [05]U.S. Food and Drug Administration. Device registration and listing — what it does and does not mean.