What Is a P-Shot: Function vs. Size, Explained Clinically

Introduction: Two Very Different Questions Men Are Actually Asking

Most men who begin researching the “P-Shot” are quietly asking one of two very different questions. The first is functional: Can I get firmer, more reliable erections and better sensitivity? The second is anatomical: Can I get bigger? These are not the same question, and conflating them is the single most common reason men spend money on the wrong procedure and walk away disappointed.

This article is written for the man who has started researching options privately and wants clinical honesty rather than marketing spin. He is often a high-achieving professional between 25 and 54 who never assumed a real solution existed, and who deserves a straight answer grounded in evidence.

The purpose here is straightforward: to explain what the P-Shot actually is, what peer-reviewed research says it can and cannot do, how its regulatory status works, who makes a good candidate, and where a fundamentally different tool, penile filler augmentation, becomes the medically appropriate choice for size goals.

What follows covers the mechanism, the evidence base, the regulatory picture, ideal candidates, limitations, and the critical distinction between functional and volumetric medicine. The claims below are anchored in clinical data and professional guidelines, not anecdote.

What Is the P-Shot? Origin, Trademark, and Clinical Definition

The P-Shot, formally the Priapus Shot, is a non-surgical, minimally invasive procedure that uses platelet-rich plasma (PRP) drawn from the patient’s own blood and injected into penile tissue. The goal is to stimulate tissue repair, improve blood flow, and enhance nerve function.

The name carries specific legal weight. “Priapus Shot” and “P-Shot” are federally registered service marks with the USPTO, developed by Dr. Charles Runels, MD, the same physician behind the “Vampire Facial.” Only providers trained and licensed through the Cellular Medicine Association can legally use the trademarked name and follow its defined protocol. A 2022 correction published in JAMA Network Open formally acknowledged this registered service mark status, which underscores an important point: the P-Shot is a defined, regulated protocol, not a generic term any clinic can apply freely.

There is also a regulatory nuance worth stating early. The PRP processing equipment (the centrifuge and collection kits) is FDA-cleared as a Class II medical device. The P-Shot as a specific treatment protocol for erectile dysfunction is not FDA-approved for that indication. These are two separate things, and the distinction matters.

Finally, PRP is not fringe science. It has an established track record in orthopedics, sports medicine, wound healing, and dentistry. Its application to sexual medicine is an extension of that broader regenerative medicine framework.

How the P-Shot Works: The Biological Mechanism

The procedure itself is efficient. Blood is drawn from the patient’s arm, then spun in a centrifuge to isolate the platelet-rich plasma. A topical anesthetic is applied to the penis, and the PRP is injected into targeted structures, including the corpus cavernosum. Start to finish, the appointment takes roughly 30 to 45 minutes.

PRP is valuable because concentrated platelets release growth factors, including PDGF, VEGF, TGF-β, and EGF. These signal the body’s own repair mechanisms. In practical terms, the P-Shot aims at three biological targets:

1. Neovascularization: stimulating new blood vessel formation to improve erectile blood flow.
2. Tissue repair: regenerating damaged smooth muscle and connective tissue within the corpus cavernosum.
3. Nerve sensitivity: potentially improving penile nerve function and tactile response.

This is a fundamentally different goal than PDE5 inhibitors such as Viagra and Cialis. Those medications temporarily increase blood flow by blocking an enzyme; they manage symptoms in the moment. The P-Shot attempts to address underlying tissue physiology.

Because PRP is autologous, meaning it comes from the patient’s own blood, serious allergic reactions are extremely rare, and the side effect profile is generally mild.

One expectation must be set clearly: results are not immediate. They emerge gradually over 2 to 12 weeks as the regenerative process takes effect. Most providers recommend waiting 6 to 8 weeks before evaluating outcomes.

What the P-Shot Is Designed to Treat

The P-Shot has its strongest theoretical and emerging evidence in a defined set of indications:

• Mild to moderate erectile dysfunction, especially vascular or nerve-related causes
• Reduced penile sensitivity
• Early-stage Peyronie’s disease (curvature and plaque)
• Post-prostate surgery rehabilitation

The Peyronie’s application is meaningful because this population has limited non-surgical options. A 2025 study of 72 participants found PRP injections helped reduce penile curvature and plaque buildup.

The post-prostatectomy use case is equally important. Men recovering from prostate surgery frequently experience nerve and vascular damage that impairs erectile function. PRP’s regenerative mechanism makes it a logical adjunct in rehabilitation protocols. In clinical practice, the P-Shot is increasingly combined with low-intensity shockwave therapy (LI-SWT) for potentially synergistic regenerative effects.

Men who have not responded adequately to PDE5 inhibitors are often considered good candidates, precisely because the P-Shot works through a distinct biological pathway.

What the P-Shot is not designed to treat: severe ED with advanced vascular disease, structural abnormalities requiring surgery, or size concerns. Those require different interventions.

The Evidence Base: What Peer-Reviewed Research Actually Shows

The honest framing is this: the P-Shot sits in a space of “promising but not yet definitive.” Multiple peer-reviewed studies show positive signals, while large-scale randomized controlled trials remain ongoing.

A 2024 meta-analysis published in PLOS ONE analyzed 12 controlled trials (991 patients) and 11 single-arm trials (377 patients). The PRP group demonstrated significantly better IIEF (International Index of Erectile Function) scores compared to controls, and the authors concluded PRP “appears effective in treating erectile dysfunction,” while noting larger trials are still needed.

A 2024 systematic review and meta-analysis in Translational Andrology and Urology, covering studies through November 2023, concluded that PRP “had some clinical effectiveness and a low incidence of side effects” and is “a safe and promising method for improving ED.”

A separate 2024 systematic review including 4 RCTs and 14 cohort studies, totaling 1,099 patients, found that studies “generally showed small to moderate benefits with mild and transient side effects and no major adverse events were reported.”

A 2023 systematic review in Sexual Medicine Reviews examined 23 studies and found that the first available randomized, placebo-controlled trials “showed promising efficacy and a lack of any adverse events.”

Translated into plain language: roughly 60 to 70 percent of men in clinical studies report some improvement in erectile function. That is meaningful, but it is not universal, and it is not dramatic in every case.

What the evidence does not yet support is equally important. The P-Shot is not established as a first-line treatment, results vary significantly by individual, and the field still needs larger, more standardized RCTs to reach definitive conclusions.

Regulatory Status Explained: Off-Label, FDA-Cleared, and What That Actually Means

Most content gets this wrong, so it is worth stating precisely. The PRP processing equipment is FDA-cleared as a Class II medical device, meaning the centrifuge and collection kits meet safety and manufacturing standards. The P-Shot protocol for erectile dysfunction is not FDA-approved for that specific indication.

That makes it an off-label use, and off-label use deserves accurate context. Off-label treatment is legal, common, and frequently evidence-supported. Physicians routinely use approved drugs and devices for indications beyond their original approval. This is standard medical practice, not a loophole.

The American Urological Association (AUA) and the Sexual Medicine Society of North America classify PRP therapy for ED as “experimental” and recommend it ideally be offered within the context of approved clinical research. Within the AUA framework, “experimental” does not mean dangerous or ineffective. It means the evidence base has not yet met the threshold for a formal treatment recommendation. Many procedures used daily in medicine carry “expert opinion” or “experimental” designations while their evidence accumulates.

Practically, this means men should seek providers who are transparent about off-label status, who hold proper training and credentials, and who set realistic expectations. A provider who claims the P-Shot is “FDA-approved for ED” is either uninformed or dishonest. The trademark licensing point is also a useful credibility signal: only providers trained through the Cellular Medicine Association can legally use the “P-Shot®” name.

Who Is, and Is Not, a Good Candidate for the P-Shot

The ideal candidate profile includes:

• Men with mild to moderate ED, particularly vascular or nerve-related
• Men with inadequate responses to PDE5 inhibitors
• Men with early Peyronie’s disease
• Men in post-prostatectomy rehabilitation
• Men seeking improved penile sensitivity

Contraindications and poor-candidate profiles include:

• Severe ED with advanced vascular disease
• Active penile infections
• Significant bleeding disorders or platelet dysfunction
• Men on anticoagulant therapy (requires medical evaluation)
• Men whose primary goal is size augmentation

That last point deserves emphasis. Men whose primary goal is size are not good candidates for the P-Shot, not because the procedure is flawed, but because it is the wrong tool for the objective.

A thorough medical consultation, including a review of ED history, medications, and underlying conditions, is essential before any PRP treatment. Results typically last 12 to 18 months, with some men reporting benefits up to 2 years, and multiple sessions can produce cumulative benefits.

What the P-Shot Does NOT Do: The Size Question, Answered Clinically

Without hedging: the P-Shot does not significantly increase penis size. It produces functional improvements, meaning firmer erections, improved sensitivity, and better stamina, not structural or volumetric changes.

Some men perceive a size difference afterward, and there is a logical reason. Improved erectile quality means fuller, firmer erections that may appear larger than a partially erect state. That is a functional improvement, not tissue augmentation. The underlying anatomy is unchanged.

This is the difference between two categories of medicine. The P-Shot is regenerative medicine: it improves how tissue functions. Penile filler is volumizing medicine: it adds physical substance beneath the skin to change appearance and girth. These are categorically different interventions.

The marketing problem is real. Some providers oversell the P-Shot as a size solution, while other sources dismiss it entirely. Both approaches fail the patient. Wanting more girth is a legitimate, common goal; it simply requires a different clinical tool. If size is the actual objective, the appropriate solution is penile filler augmentation.

When Size Is the Goal: Understanding Penile Filler Augmentation

Filler phalloplasty is the medically appropriate tool when girth augmentation is the primary objective. It is not a competitor to the P-Shot; it is a different solution to a different problem.

The mechanism: hyaluronic acid-based dermal fillers are injected beneath the penile skin to add volume and girth. The results are immediate, visible, and physically measurable. A 2020 multicenter randomized controlled trial in the Journal of Clinical Medicine followed 67 men over 18 months and found that both HA and polylactic acid fillers produced significant penile girth increases and higher satisfaction scores, with minor adverse events in fewer than 10 percent of patients.

Realistically, filler augmentation can achieve immediate penis enhancement results of up to 1 to 1.5 inches in girth, with results visible immediately and a natural appearance and feel in both flaccid and erect states, while normal sensation and function are maintained.

What it does not do is address erectile function, blood circulation, or nerve sensitivity. It is purely volumetric. Men with both ED and size goals may benefit from a combined approach discussed with their provider.

One meaningful safety advantage: hyaluronic acid fillers can be dissolved with hyaluronidase if needed, which is not possible with permanent surgical options.

Regarding cost, filler phalloplasty at Stoller Medical Group starts at $7,500 and increases based on desired results. Pricing is by syringe, with most men starting at a minimum of 10 syringes and averaging 15 syringes during their first procedure. This reflects the clinical expertise and medical-grade materials involved.

P-Shot vs. Penile Filler: A Side-by-Side Clinical Comparison

The point of this comparison is to help a man match the procedure to his actual goal, not to advocate for one over the other.

Some men have both functional concerns and size goals. In those cases, a provider experienced in both modalities can discuss sequencing or a combination approach. A third modality, low-intensity shockwave therapy (LI-SWT), is sometimes combined with the P-Shot for synergistic regenerative effects.

Neither procedure is superior in absolute terms. The right procedure is the one that matches the patient’s actual clinical objective.

Safety Profile, Side Effects, and What to Expect During Recovery

For the P-Shot, common side effects are minor and temporary: pain, bruising, and swelling at injection sites. Because PRP is autologous, serious allergic reactions are extremely rare. Across 2024 meta-analyses totaling more than 1,000 patients, the consistent finding was that “no major adverse events were reported,” which is a meaningful safety signal.

For penile filler, the side effects are similar (bruising, swelling, temporary tenderness), with minor adverse events in fewer than 10 percent of patients in the 2020 RCT. The reversibility of HA filler adds an additional layer of safety.

Provider selection directly affects safety outcomes. Training, anatomical knowledge, sterility protocols, and penis enlargement medical-grade materials determine results. This is not a procedure to choose on price alone.

Recovery differs between the two. The P-Shot has essentially no downtime, and men return to normal activities quickly. Penile filler typically involves 7 to 10 days before resuming sexual activity. For either procedure, a thorough consultation, full medical history review, and informed consent process are non-negotiable.

How to Evaluate a Provider: Questions Every Man Should Ask

Provider selection is the single most important variable in both safety and outcome quality.

For P-Shot providers, ask:

• Are you licensed through the Cellular Medicine Association to use the trademarked P-Shot® protocol?
• What is your experience volume and training in penile anatomy?
• How do you discuss the off-label and experimental status with patients?

For filler phalloplasty providers, ask:

• What is your total procedure volume in this specific anatomical location?
• What filler product do you use, and what is its biocompatibility profile?
• What is your protocol for managing complications?
• Do you use a staged treatment philosophy?

General questions for any provider:

• What are realistic outcomes for my specific situation?
• What contraindications would make me a poor candidate?
• What does the follow-up process look like?

Red flags to avoid: providers who claim the P-Shot is FDA-approved for ED, who guarantee dramatic size increases from the P-Shot, who offer single-session dramatic filler volumes without staged assessment, or who cannot clearly explain the regulatory status of what they offer.

Board-certified physicians with dedicated experience in male aesthetic medicine and advanced training in penile anatomy represent the appropriate standard of care.

Conclusion: Matching the Right Tool to the Right Goal

The core distinction is simple once stated plainly. The P-Shot is a regenerative medicine procedure targeting erectile function, sensitivity, and tissue health. It is not a size augmentation tool. Penile filler augmentation is a volumizing procedure that adds measurable girth. It is not a treatment for erectile dysfunction.

The P-Shot has a growing, peer-reviewed evidence base showing functional benefits for the right candidates, but it remains classified as experimental by the AUA and should be approached with calibrated expectations. Both goals, improving erectile function and increasing girth, are legitimate and addressable. The key is matching the intervention to the objective.

Men navigating this research often do so privately, with limited access to trusted information. Clinical honesty, including a frank explanation of what a procedure cannot do, is the foundation of a trustworthy patient relationship. The appropriate next step is a consultation with a qualified, experienced provider: not to be sold a procedure, but to have an honest conversation about which tool, if any, fits the individual’s situation and anatomy.

Ready to Get Clinically Honest Answers? Schedule a Consultation

A consultation should be an information-gathering conversation, not a sales appointment. For men who have quietly wondered whether a real solution exists, that first honest conversation is often the most valuable step.

Stoller Medical Group, operating as Penis Enlargement New York City, brings over 15,000 procedures performed and the expertise of Dr. Roy B. Stoller, whose 25-plus years in aesthetic and restorative medicine include a dedicated focus of 5 years specifically on non-surgical male genital enhancement. The practice’s philosophy is to identify the right solution for each individual’s specific objective, whether that is functional improvement, girth augmentation, or a combined approach, rather than applying a one-size-fits-all protocol.

Free consultations are offered across five locations for convenience throughout the Northeast and Midwest:

• Manhattan, NY: 515 Madison Avenue, Suite 1205
• Long Island, NY: 366 N Broadway, Suite LE2, Jericho
• Albany, NY: 1202 Troy Schenectady Road, Latham
• Pennsylvania: 1212 Baltimore Pike, Chadds Ford
• Minnesota: 2121 Cliff Drive, Suite 210, Eagan

Clinically sound, professionally administered options exist. The first step is simply an honest conversation.