Chapter 01
Why erections change after the operation
Radical prostatectomy removes the prostate and seminal vesicles. The nerves responsible for erections, called the cavernous nerves, sit in a bundle that runs directly alongside the prostate capsule. Even an experienced surgeon using a nerve-sparing technique has to work within millimetres of them, and stretching, heat, bruising or traction is often enough to stop them signalling for a long period.
That temporary loss of nerve function is called neuropraxia. The nerve is not necessarily severed, but it is not conducting. Recovery, when it happens, is slow. Published follow-up commonly extends to twelve months and beyond, and some men continue to see change into a second year.
The important part is what happens to the penis while the nerves are quiet. This is the reasoning behind the whole concept of rehabilitation.
Nerve signalling stops
The chemical signal that relaxes the smooth muscle inside the erectile bodies is interrupted, so erections do not occur on demand.
Night-time erections disappear
Healthy men have several erections during sleep. These are not about sex. They are how the erectile tissue receives a regular supply of oxygen-rich blood.
The tissue spends its time low on oxygen
Without those regular refills, the erectile bodies sit in a low-oxygen state for months rather than hours.
Muscle is gradually replaced by scar-like tissue
Prolonged low oxygen is associated with loss of smooth muscle and a build-up of collagen. Elastic tissue becomes stiffer, less compliant tissue.
The penis becomes shorter and harder to inflate
Stiffer tissue does not expand or trap blood as well. This is why length loss and difficulty holding an erection can persist even after nerves recover.
Read in that order, the logic of rehabilitation is straightforward. If the damage during the recovery window is driven by tissue sitting without oxygen, then getting blood into that tissue regularly is worth attempting while you wait for the nerves.
Chapter 02
Where a vacuum device fits
Penile rehabilitation is the general term for anything done in the months after surgery to protect erectile tissue while nerve function recovers. There is no single agreed protocol, and different centres favour different combinations. The usual candidates are oral tablets, injections, and vacuum erection devices.
The distinction that matters after prostatectomy is how each option produces its effect.
Why tablets often disappoint early
PDE5 inhibitors such as sildenafil and tadalafil do not create an erection by themselves. They amplify a signal that the nerves have to start. If the cavernous nerves are not conducting, there is often little signal to amplify, which is why many men find tablets far less effective in the first months after surgery than they expected. This is not a sign that the drug will never work. It usually reflects where the nerves are in their recovery.
Why a VED behaves differently
A vacuum erection device does not use the nerve pathway at all. It lowers air pressure around the penis, and that pressure difference draws blood into the erectile bodies mechanically. Because the mechanism is physical rather than chemical, it can fill the tissue at a stage when nerve-dependent options are still unreliable. That property is the entire reason the device appears so consistently in post-prostatectomy literature.
It is worth being precise about the two different ways a VED gets used after surgery, because they are often confused:
| Use | Goal | Constriction ring | Typical pattern in published protocols |
|---|
| Tissue conditioning |
Draw oxygenated blood into the erectile bodies while nerves recover |
Not used |
Short sessions, often daily, blood allowed to drain between repetitions |
| Erection for intercourse |
Produce and hold an erection firm enough for sex |
Used, with a strict time limit |
As desired, ring removed well within the manufacturer's stated limit |
Those are different activities with different equipment and different risks. A rehabilitation protocol is usually about the first. Being able to have sex again is usually about the second. Most men end up doing both, at different points in their recovery.
Chapter 03
What the evidence does show
Vacuum devices have four decades of published use. The findings most relevant to men after prostatectomy are these.
84.5%
Efficacy in men using a VED after radical prostatectomy, the highest subgroup result in a meta-analysis of 1,065 patients across 18 studies.
Zhang et al., Int J Impot Res 2025 · PMID 405422514
3% vs 48%
Among men who used a VED on more than half of possible days, 3% lost at least 1 cm; the authors compared this with a 48% rate from prior post-prostatectomy studies.
Dalkin & Christopher, Int J Impot Res 2007 · PMID 176572105
12 months
The follow-up period across post-prostatectomy protocols, typically beginning about one month after surgery.
Narrative review, Int J Impot Res 2025 · PMID 404424856
Treatment option
The AUA recommends informing men with ED about VEDs as a treatment option. Fifth ICSM guidance generally places VEDs after PDE5 inhibitors, while its VED-specific consensus recognizes primary or combination use for selected patients, including after prostatectomy.
AUA Guideline 2018 · Fifth ICSM recommendations 20252,3,9
The 2025 narrative review summarises the pattern across studies plainly: VED therapy is typically started at one month after the operation and continued through a twelve-month follow-up period, with studies showing improvement in erectile function scores, conservation of penile length, and satisfactory intercourse compared with controls.6
Combination approaches are also discussed in this literature. A clinician may pair a vacuum device with a PDE5 inhibitor, and the 5th International Consultation on Sexual Medicine supports combination strategies in appropriate patients.3 That decision belongs to the prescriber, not to a website.
Chapter 04
What the evidence does not show
This section matters as much as the one above it. Marketing in this category routinely overstates the case, and men recovering from cancer surgery deserve a straight account of the limits.
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It does not show that a VED restores natural, unassisted erections.
Devices reliably produce erections while in use. Whether that use meaningfully improves spontaneous erectile function later is the least settled question in the field, and reviews say so directly.
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It does not show that one protocol is best.
Start times, session length, daily repetitions and total duration vary between studies. There is no single validated schedule.
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It does not show equal results for every man.
Nerve-sparing status, surgical technique, age, baseline erectile function, diabetes and cardiovascular health all affect recovery. Group averages do not predict an individual outcome.
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It does not extend to every kind of prostate treatment.
Rehabilitation evidence after radiotherapy, brachytherapy or focal therapy is not the same as the evidence after radical prostatectomy. Do not assume the protocols transfer.
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It does not establish any specific product.
The research studies the device category. External penile rigidity devices are classified under 21 CFR 876.5020, and that category reference does not state that a particular product is FDA cleared or approved.1
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Length preservation is not enlargement.
Preserving what surgery would otherwise take is a different claim from adding size to a healthy penis. Findings from one do not support the other.
Chapter 05
What published protocols look like
Read this before the table
The schedule below describes what appears in published studies. It is not a prescription and it is not permission to begin. Your surgeon knows your nerve-sparing status, your healing, your catheter timeline and your bleeding risk. Do not start vacuum therapy, and do not resume it after any complication, without their clearance.
If you have been given a specific protocol by your own urology team, follow theirs rather than anything you read here.
| Element | What the literature commonly describes |
|---|
| Start | Around one month after surgery in most protocols, after catheter removal and with the surgeon's clearance |
| Frequency | Daily, or close to daily, for the conditioning phase |
| Session | Short. Blood is drawn in, held briefly, then allowed to drain, and the cycle is repeated a small number of times |
| Ring | Not used during conditioning. Used only when the goal is intercourse, and removed within the manufacturer's stated time limit |
| Duration | Twelve months is the follow-up period in the post-prostatectomy literature |
| Pressure | Comfortable and gradual. Pain is a stop signal, not a target to push through |
| Combination | A clinician may add a PDE5 inhibitor. That is a prescribing decision |
The practical difficulty with all of this is not complexity. It is persistence. A twelve-month daily routine is a long commitment during a period when most men are also dealing with continence recovery, follow-up PSA tests and the emotional weight of a cancer diagnosis. Adherence is the variable that most often separates the men who get a result from the men who do not.
Chapter 06
Safety, side effects and who should not use one
Talk to a clinician first if any of these apply
Anticoagulant or antiplatelet medication, a bleeding or clotting disorder, sickle cell disease or trait, a history of priapism, reduced penile sensation, active infection or unhealed wounds in the area, or significant penile curvature or Peyronie's disease. None of these are automatically disqualifying, but all of them change the risk calculation and need a clinician's input.
Side effects reported with vacuum therapy
Bruising and small red spots on the skin, a sensation of coldness or a bluish tint at the tip, temporary numbness, discomfort or pain, and a feeling that the erection pivots at the base rather than being rigid throughout. Most are mild and settle. They become a reason to stop when they persist, worsen or hurt.
Stop and seek medical advice
Stop using the device and contact a clinician if you experience pain that does not settle quickly, skin that stays discoloured, numbness that does not resolve, any bleeding, or a new or worsening bend in the penis.
Two things that surprise men after prostatectomy
Orgasm is dry. The prostate and seminal vesicles produce most of the fluid in ejaculate, and both are removed during the operation. Orgasm remains possible without ejaculation. This is expected after the surgery and is not caused by vacuum therapy.
Some men leak urine at orgasm. This is common enough after prostatectomy to have its own name, climacturia. It often improves with pelvic floor rehabilitation. It is worth raising with your team rather than living with quietly.
Chapter 07
Questions worth asking your urologist
Consultations after surgery are short and cover a lot of ground. These are the questions that tend to produce the most useful answers about erectile recovery.
Were my nerves spared, and on which side?Bilateral, unilateral and non-nerve-sparing surgery carry different outlooks. This single answer reframes everything else.
When may I start vacuum therapy?Ask for a specific date or milestone rather than a general reassurance.
What schedule do you want me on?Sessions per day, repetitions, and for how many months.
Should I be taking a PDE5 inhibitor as well?And if it does not seem to work at first, is that expected at this stage?
Do any of my medications change the risk?Particularly anticoagulants and antiplatelets.
What should make me stop and call you?Get the specific warning signs for your situation.
What is realistic for me, and by when?An honest timeline from the person who performed the operation is worth more than any average.
Is a referral to sexual medicine available?Many centres have a dedicated service, and men are often not told.
Common questions
Frequently asked
When can I start using a VED after prostatectomy?
Published protocols commonly begin about one month after surgery, after the catheter is out. The actual date has to come from your surgeon, because it depends on your healing, your nerve-sparing status and your bleeding risk. Do not start before you have been cleared.
Does a VED restore natural erections after prostate surgery?
The evidence supports using a VED to produce erections, to make intercourse possible, and to reduce loss of penile length. Evidence that it restores spontaneous, unassisted erectile function is uncertain, and reviews of this literature say so directly. Treat any claim that a pump will bring back natural erections as going beyond what has been shown.
Why do ED tablets not work for me after surgery?
PDE5 inhibitors amplify a signal that the cavernous nerves have to start. If those nerves are not conducting yet, there is little signal to amplify. This is common in the early months and does not mean the medication will never help. A vacuum device works mechanically instead, which is why it can produce an erection during the same period. Discuss the combination with your prescriber.
Will a VED stop my penis from getting shorter?
Length preservation is the best-supported benefit in this literature. In one study, 3% of men who used a VED on more than half of possible days lost 1 cm or more of length. The authors compared that result with a 48% rate reported in prior post-prostatectomy studies. That is preservation of existing length, not enlargement, and results vary between individuals.
How long do I need to keep using it?
Twelve months is the follow-up period in the post-prostatectomy literature, with daily or near-daily use during the conditioning phase. It is a long commitment, and adherence is the factor that most often separates men who see a result from those who do not. Your own team may set a different schedule.
Do I use a constriction ring during rehabilitation?
Generally no. Conditioning sessions draw blood in and let it drain again, so no ring is used. A ring is for holding an erection for intercourse, and it must come off within the time limit stated in your device manual. Confirm both uses with your clinician.
Is vacuum therapy safe if I take blood thinners?
Anticoagulant and antiplatelet medication, bleeding disorders and sickle cell disease are all relative contraindications for vacuum therapy. That does not always mean no, but it does mean the decision belongs to a clinician who knows your medication list. Raise it before you buy a device.
Does this apply after radiation rather than surgery?
Not directly. Erectile dysfunction after radiotherapy or other pelvic treatment develops differently and on a different timeline, and the rehabilitation evidence is not the same as the evidence after radical prostatectomy. Ask your oncology or urology team what applies to your treatment.
Why is there no ejaculate when I orgasm?
The prostate and seminal vesicles produce most of the fluid in ejaculate and both are removed during radical prostatectomy. Orgasm without ejaculation is the expected outcome of the surgery. It is not caused by vacuum therapy and it is not a sign that anything has gone wrong.
References
- FDA, 21 CFR §876.5020, External Penile Rigidity Devices. eCFR
- American Urological Association. Erectile Dysfunction Guideline (2018). J Urol 200(3):633-641.
- Stern et al. 5th International Consultation on Sexual Medicine recommendations on the management of erectile dysfunction. Sex Med Rev, 2025. PMID 40753504
- Zhang et al. Efficacy of vacuum erection devices for erectile dysfunction: a systematic review and meta-analysis. Int J Impot Res, 2025. PMID 40542251
- Dalkin BL, Christopher BA. Preservation of penile length after radical prostatectomy: early intervention with a vacuum erection device. Int J Impot Res, 2007. PMID 17657210
- The role of vacuum erection device and penile traction therapy after radical prostatectomy, narrative review. Int J Impot Res, 2025. PMID 40442485
- Yuan J, Hoang AN, Romero CA, Lin H, Dai Y, Wang R. Vacuum therapy in erectile dysfunction, science and clinical evidence. Int J Impot Res, 2010. PMID 20410903
- European Association of Urology. Sexual and Reproductive Health, Management of Erectile Dysfunction. uroweb.org
- Vacuum erectile devices for erectile dysfunction: recommendations from the 5th International Consultation on Sexual Medicine. Sex Med Rev, 2025. PMID 39957431
Medical disclaimer
External penile rigidity devices, the federal category that includes vacuum erection systems, are classified under 21 CFR §876.5020. A category reference does not state that a particular SmartTract product is FDA cleared or approved.
This page is educational and is not a substitute for professional medical advice, diagnosis or treatment. It describes what has been reported in published research about the vacuum erection device category. It does not describe SmartTract-specific clinical trials, and it is not a rehabilitation protocol for any individual.
Consult your treating surgeon or urologist before beginning or resuming vacuum therapy after prostate surgery, and particularly if you have a bleeding disorder, sickle cell disease, reduced penile sensation, a history of priapism, or take anticoagulant medication. Stop use and seek medical guidance if pain, unusual discoloration, numbness or injury occurs.
