Penile implants: types, how they work, and who considers them

Status: Inflatable penile implants are Class III medical devices that need FDA premarket approval; semi-rigid rod implants are Class II medical devices. Source: FDA device classification rules, 21 CFR 876.3350 and 876.3630, checked 2026-10-17.

In short: a penile implant, also called a penile prosthesis, is a device a surgeon places inside the penis so a man with erectile dysfunction (ED) can have an erection when he wants one. It is one of the five treatments the American Urological Association (AUA) says every man with ED should be told about. It is also the only one that is permanent in practice. This page explains the types, how they work, who tends to consider one, how it compares with injections and a vacuum pump, and what the satisfaction studies do and do not show. It does not tell you whether an implant is right for you. That conversation belongs with a urologist who performs the surgery.

What is a penile implant?

A penile implant is a medical device placed inside the penis during surgery that makes the penis rigid enough for sex. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) describes it as a device that makes the penis erect “either using a pump in the scrotum or a rod that you can control on your own” (NIDDK, Treatment for ED).

The AUA guideline gives it a strong recommendation as an option men should hear about: “Men with ED should be informed regarding the treatment option of penile prosthesis implantation, including discussion of benefits and risks/burdens” (Statement 18, Strong Recommendation, Evidence Grade C, in the AUA Erectile Dysfunction Guideline). The grade C refers to the kind of studies behind it, mostly observational and retrospective, not to how well implants work. Our guide to how to read ED evidence explains those grades.

An implant treats the erection itself, not the cause of ED. NIDDK notes that clinicians treat the underlying cause of ED when they can, and that most people with ED do not need surgery (NIDDK, Treatment for ED).

What types of penile implant are there?

There are two main families: inflatable implants and malleable, or semi-rigid, rod implants. The AUA guideline lists malleable (non-inflatable) models and two-piece or three-piece inflatable models as the devices currently available (AUA guideline, Statement 18 discussion). The FDA classifies the two families separately, which is why the status line above names both (21 CFR 876.3350; 21 CFR 876.3630).

Sources for the table: the FDA device descriptions (21 CFR 876.3350; 21 CFR 876.3630) and the AUA discussion of Statements 18 and 19 (AUA guideline PDF).

How does a penile implant work?

An inflatable implant works by moving fluid. The FDA’s own description of the device is two inflatable cylinders in the penis, connected to a fluid-filled reservoir in the abdomen and a manual pump placed under the skin of the scrotum; “when the cylinders are inflated, they provide rigidity to the penis” (21 CFR 876.3350). Working the pump moves fluid from the reservoir into the cylinders. Unlike rods, an inflatable device can also be deflated, so the penis can be soft at other times (AUA guideline, Statement 19 discussion).

A malleable implant has no fluid and no pump. The FDA describes it as a pair of semi-rigid rods implanted in the erectile chambers of the penis to provide rigidity (21 CFR 876.3630). The AUA says these models “can be bent to lay flat against the groin,” but they “cannot be ‘deflated’” (AUA guideline, Statement 19 discussion).

Either way, the device supplies rigidity, not arousal. The AUA notes that inflating a prosthesis does not fill the head of the penis with blood, which is one reason some men feel the penis looks shorter afterward (AUA guideline, Statement 18 discussion). That is different from how ED pills work, which our guide to ED treatment options beyond pills explains side by side.

How is a penile implant sized?

Implant cylinders are not one size, and cylinder length is chosen at the time of surgery. The AUA cites some evidence that surgeons who implant often use longer cylinders than surgeons who implant less often, and notes that several strategies have been studied to maximize length and girth, but the panel found “insufficient data on specific approaches and techniques” to give clinical guidance on them (AUA guideline, Statement 18 discussion).

An implant is not a way to make the penis larger. The AUA says men with prior scarring, fibrosis or loss of erectile tissue should be told an implant “is unlikely to restore penile dimensions” to what they were before, and it tells clinicians to discuss and document length expectations before surgery. In the studies it reviewed, some men perceived the penis as shorter after surgery, while measured changes were small (AUA guideline, Statement 18 discussion). Device choice and sizing are questions to put to the surgeon directly.

Who considers a penile implant?

Men consider an implant most often after other ED treatments have not worked or have not suited them. NIDDK says surgery may be considered “if you have tried all other options and your ED does not improve” (NIDDK, Treatment for ED). The AUA frames it more broadly: with shared decision-making, “it is valid for men to begin with any type of treatment, regardless of invasiveness or reversibility,” and men may also choose not to treat ED at all (AUA Erectile Dysfunction Guideline).

The AUA says implants have been placed successfully both in the general ED population and in a variety of special populations; the studies it cites include men after radical prostatectomy and men with spinal cord injury (AUA guideline, Statement 18 and references). Our page on ED after prostate treatment covers the broader picture. Some situations shape the choice of device:

• Peyronie’s disease. The AUA’s Peyronie’s guideline says clinicians may offer implant surgery to men with Peyronie’s disease and ED, or a penile deformity severe enough to prevent sex, when medicines or a vacuum device have not been enough, and that an inflatable device should be used in that setting (Statements 20 and 22, Nehra et al., Peyronie’s Disease: AUA Guideline). Our Peyronie’s disease page explains the condition, and our guide to Peyronie’s disease treatment goes through the other options.
• Limited manual dexterity. The AUA says two-piece inflatable models are easier to work than three-piece models, and that a malleable implant can be more appropriate in this situation (AUA guideline, Statement 19 discussion).

There is one firm stop sign. The AUA says implant surgery “should not be performed in the presence of systemic, cutaneous, or urinary tract infection” (Statement 20, AUA Erectile Dysfunction Guideline).

How does an implant compare with injections or a vacuum pump?

The biggest difference is that an implant is permanent in practice, while injections and a vacuum pump can be stopped at any time. The AUA says the implant choice “is best conceptualized as irreversible; although prostheses can be removed, it is unlikely that a man’s penis will be reliably responsive to other ED therapies after prosthesis explant” (AUA guideline, Statement 18 discussion).

Sources for the table: AUA Statements 13, 16, 17 and 18 (AUA Erectile Dysfunction Guideline) and NIDDK’s description of vacuum devices and injection side effects (NIDDK, Treatment for ED).

Head-to-head evidence is thin. One small U.S. study of 85 men at a single urology practice, followed for about 19.5 months, found that the 32 men with an implant had higher treatment satisfaction and erectile function scores than the men using sildenafil or injections (Rajpurkar and Dhabuwala, J Urol 2003). The men were not randomly assigned, so the study cannot show that an implant would suit any one man better.

What are the main risks of a penile implant?

A serious risk is infection, which usually means the device has to come out. The AUA says infection typically happens within the first three months and that, with devices that carry infection-inhibiting coatings, most series report infection rates of 1% to 2% (AUA guideline, Statement 18 discussion). If an infected implant is removed and a new one placed later, the AUA says the second operation is complex and that shortening, a change in shape and loss of sensation become more likely.

Other risks the AUA describes from the same review (AUA guideline PDF):

• Early problems after surgery. Swelling or bruising, injury to nearby tissue and short-term trouble passing urine were reported, were rarely serious, and generally settled with supportive care. In the panel’s experience, most men have some pain that resolves within one to three months.
• Erosion. If the tissue at the tip of the penis weakens, a cylinder can move into the head of the penis and need surgical repair. Average rates were 2.5% for inflatable and 4.1% for malleable models.
• Mechanical failure. This is most common with inflatable models, often from a leak in the tubing. Recent reports cited by the AUA suggest 90% to 95% of men still have a working device 10 years after surgery.

A systematic review of three-piece inflatable implants found removal rates were generally below 10% and infection rates typically under 5%, with wide variation between devices and studies (Lo Re et al., Int J Impot Res 2026). Recovery time, the first weeks after surgery and when the device can be used are part of the counseling the AUA calls for in Statement 19.

What satisfaction data exists for penile implants?

Most men in published studies report being satisfied, with inflatable models scoring higher than malleable ones. Across the studies the AUA panel reviewed, mean satisfaction was 86.2% for inflatable models and 75.1% for malleable models (AUA guideline, Statement 18 discussion).

Read these numbers with their limits in view. The AUA describes the evidence as observational and mostly retrospective, with many studies not using validated questionnaires and many patients lost to follow-up (AUA guideline, Statement 18 discussion). The quality-of-life review rated most of its included studies at serious or high risk of bias (Manfredi et al., 2024). Satisfaction figures describe groups of men who chose surgery, not a promise for any one person. The AUA’s own conclusion is that thorough counseling about short and long-term expectations is essential, so that the outcome matches what a man and his partner expect.

Sources

1. Burnett AL, et al. Erectile Dysfunction: AUA Guideline (2018). American Urological Association
2. Erectile Dysfunction: AUA Guideline, full text with discussion and appendices (PDF). American Urological Association
3. NIDDK. Treatment for Erectile Dysfunction
4. 21 CFR 876.3350, Penile inflatable implant. eCFR
5. 21 CFR 876.3630, Penile rigidity implant. eCFR
6. Nehra A, et al. Peyronie’s Disease: AUA Guideline. J Urol. 2015 (PMC)
7. Corona G, et al. Long-term penile prosthesis couple’s satisfaction: a systematic review and meta-analysis. Andrology. 2025;13(3):610-623
8. Satwikananda H, et al. Efficacy and safety of malleable penile prosthesis compared to inflatable penile prosthesis in erectile dysfunction patients. Arch Ital Urol Androl. 2024;96(2):12353
9. Lo Re M, et al. Removal rate and mechanical failure in penile prosthesis implantation: a systematic review. Int J Impot Res. 2026;38(3):226-237
10. Manfredi C, et al. Quality of life and sexuality with penile prosthesis: a systematic review and pooled analysis. Minerva Urol Nephrol. 2024;76(2):166-175
11. Rajpurkar A, Dhabuwala CB. Comparison of satisfaction rates and erectile function in patients treated with sildenafil, intracavernous prostaglandin E1 and penile implant surgery. J Urol. 2003;170(1):159-163