Hyaluronic Acid vs. Other Penile Fillers: Which Is Safest?

Content reviewed by Dr. Sean Rice, FRCSC
Board-Certified Plastic Surgeon · Urosculpt™ Certification Board
Published March 3, 2026 · 8 min read

Not all penile fillers are created equal. As demand for non-surgical penile enhancement continues to grow, men are confronted with a range of options — from injectable hyaluronic acid and polylactic acid to permanent materials like PMMA and silicone implants. The differences in safety, efficacy, longevity, and reversibility between these options are significant. This article examines the clinical evidence behind each major filler type used in penile girth enhancement.

1. Hyaluronic Acid (HA)

Hyaluronic acid is a naturally occurring substance found throughout the human body, particularly in the skin, joints, and connective tissues. It was approved by the FDA for cosmetic use in 2003 and has become the most widely used injectable filler worldwide. In penile enhancement, HA is injected beneath the skin to increase girth, producing results visible immediately.

The key advantages of HA are its biocompatibility, favourable safety profile, and full reversibility. If a patient is dissatisfied with the result or develops a complication, the enzyme hyaluronidase can dissolve the filler quickly and safely. A 2023 systematic review and meta-analysis comparing HA to polylactic acid found that HA produced greater girth enhancement (mean increase of 2.1cm vs. 1.6cm) and higher patient satisfaction, with no serious adverse events in either group.¹

The most commonly reported complications with HA are minor and manageable: temporary asymmetry, filler migration (particularly in uncircumcised men), and palpable nodules — all treatable with hyaluronidase or manual redistribution. Infection rates in well-controlled clinical settings are low, typically below 2%.² Results generally last 18 to 24 months, depending on the product and individual metabolism.

2. Polylactic Acid (PLA)

Polylactic acid works differently from HA. Rather than adding volume directly, PLA stimulates the body’s own collagen production through a controlled inflammatory response. This biostimulatory mechanism means results develop gradually over several weeks rather than appearing immediately.

A multi-centre randomised trial comparing HA and PLA for penile augmentation found that both produced significant girth enhancement at 24 weeks, but HA achieved greater absolute girth increases. Satisfaction levels improved significantly in both groups.³

However, PLA has a critical limitation: it is not easily reversible. Unlike HA, there is no enzyme that can dissolve PLA. If a patient develops nodules, asymmetry, or is simply unhappy with the result, management options are limited and may require surgical excision. For a cosmetic procedure where patient preferences may change over time, this lack of a safety net is a significant drawback.

3. Polymethylmethacrylate (PMMA)

PMMA is a permanent, non-absorbable synthetic polymer. After injection, connective tissue encapsulates the microspheres, creating volume that the body’s enzymes cannot break down. This permanence is sometimes marketed as an advantage — one treatment, lasting results.

In practice, permanence is a double-edged sword. A 2024 prospective study comparing HA, PLA, and PMMA found that while PMMA produced the greatest absolute girth increase, it also had the lowest improvement in patient satisfaction scores and a higher complication profile.⁴ Complications with PMMA can include chronic granulomatous reactions, nodule formation, and migration — and because the material cannot be dissolved or easily removed, management often requires surgical excision. A 2025 review of penile enhancement complications emphasised that permanent fillers carry inherently higher long-term risks than absorbable alternatives.⁵

4. Autologous Fat Transfer

Fat transfer involves harvesting fat from another area of the body (typically the abdomen or thighs) via liposuction, processing it, and injecting it into the penile shaft. Because the material is the patient’s own tissue, there is no risk of allergic reaction or foreign body response.

The major limitation is unpredictable resorption. The body reabsorbs a variable percentage of the transferred fat — sometimes 30%, sometimes 70% — making outcomes highly inconsistent. Multiple studies have reported irregular residual fat nodules, skin deformity, and scarring as common complications. A comprehensive 2025 review noted that while fat transfer remains an option, its unstable resorption rates have led many providers to prefer injectable HA fillers.⁶

5. Silicone Implants (Penuma)

The Penuma implant is the only FDA-cleared device specifically designed for cosmetic penile enhancement. It is a crescent-shaped silicone sleeve placed surgically beneath the skin of the penile shaft. Unlike injectable fillers, this is a fully surgical procedure requiring anaesthesia and several weeks of recovery.

Penuma offers permanent structural enhancement but carries surgical risks including infection, implant migration, erosion through the skin, and the need for revision surgery. A multi-institutional study reported that while most patients were satisfied, complication rates were higher than those associated with injectable HA, and management of complications could be complex.⁷

6. Head-to-Head Comparison

When evaluating these options, the factors that matter most to patients are safety, reversibility, downtime, and predictability of results.

HA stands out as the option with the best overall balance. It is the only major filler type that is fully reversible with hyaluronidase, has the most robust safety data in the penile enhancement literature, provides immediate visible results, requires no surgical incisions or general anaesthesia, and involves minimal downtime. For a detailed comparison, see our comparison of penile enhancement options.

PLA is a reasonable alternative for patients seeking a biostimulatory approach, but its lack of reversibility is a significant drawback. PMMA and silicone offer permanence but at the cost of higher complication risk. Fat transfer is autologous but suffers from unpredictable resorption.

7. Why Urosculpt™ Uses HA Exclusively

The Upsize™ proprietary procedure, performed by Urosculpt™ certified physicians, exclusively uses premium hyaluronic acid filler. This decision is evidence-based: HA offers the most favourable combination of safety, efficacy, predictability, and reversibility among all available options. The standardized protocol — using a proprietary cannula-based technique — further minimises risk and ensures even, natural-looking results.

For men considering penile enhancement, the choice of filler material is one of the most consequential decisions. We encourage prospective patients to research their options, prioritise reversibility and safety over permanence, and choose a qualified, certified provider who uses evidence-based materials and techniques.

This article is for informational purposes only and does not constitute medical advice. Dermal fillers for penile enhancement are used off-label and have not been specifically approved by Health Canada or the FDA for this indication. Individual results vary. Always consult with a qualified physician before undergoing any medical procedure.