What to Do When Viagra and Cialis Don’t Work

Roughly half of men who initially fail on Viagra (sildenafil) or Cialis (tadalafil) can be “salvaged” with adjustments that do not require moving to a different treatment at all. That is the surprising finding from multiple studies of so-called non-responders, and it means the first thing to do when these pills seem ineffective is not to abandon them but to figure out whether you were set up to succeed in the first place. Beyond that, a genuine non-responder still has a range of effective options, from self-administered injections and urethral pellets to vacuum devices, shockwave therapy, and penile implants, each with real evidence behind it.

Make Sure the Pills Actually Had a Fair Trial

Before concluding that oral medications do not work for you, it is worth asking a blunt question: were you using them correctly? A study of 100 men classified as sildenafil non-responders found that 56 of them had never given the drug a proper chance. Among the problems identified, 45 had never tried the highest recommended dose, 32 had taken the pill on a full stomach right after a meal, 22 had taken it immediately before sex rather than allowing time for absorption, and 12 did not realize that sexual arousal is still required for the drug to work.¹ These are not obscure technicalities. A fatty meal can dramatically delay absorption of sildenafil, and the drug needs at least 30 to 60 minutes to reach effective blood levels.

When men who had previously failed on sildenafil received proper counseling on timing, dosing, expectations, and the importance of making at least eight attempts, about 55% of them became successful with the same drug they had given up on.² A separate real-world study of tadalafil and vardenafil non-responders found similar patterns: after correcting inappropriate use and trying strategies like taking the medication in a fasted state or using it daily, the overall salvage rate was around 46 to 52%.³

If you have only tried one PDE5 inhibitor, switching to another is also reasonable. These drugs differ in how long they last and how sensitive they are to food. Tadalafil, for instance, has a much longer window of action and is less affected by meals than sildenafil, which matters if spontaneity or timing has been part of your difficulty. A genuine pharmacological non-response to all PDE5 inhibitors at maximum dose, taken correctly and tried multiple times, is a different situation from a premature conclusion based on one or two disappointing evenings.

Check for Low Testosterone

One of the most commonly overlooked reasons PDE5 inhibitors fall short is low testosterone. This is not a rare scenario. Screening studies have found a meaningful prevalence of low testosterone specifically among men who failed prior sildenafil treatment.⁴ The connection is not just about desire. Testosterone is directly involved in the biochemical pathway these drugs depend on. In testosterone-deficient tissue, the enzyme that produces nitric oxide and even the target enzyme the pills act on (PDE5) are both reduced. Without adequate testosterone, the drug literally has less molecular machinery to work with.

The clinical evidence on this is strong. In a study of men whose erectile function remained poor despite testosterone replacement therapy bringing their levels back to normal, adding sildenafil on top of the testosterone turned every one of them into a responder.⁵ The combination worked where neither treatment alone had been sufficient. If you have never had your testosterone checked, or if a doctor prescribed Viagra or Cialis without testing your hormone levels first, this is a conversation worth having.

Why Vascular Disease Makes Pills Less Effective

PDE5 inhibitors work by amplifying the effect of nitric oxide, a molecule your blood vessels produce to relax and dilate. When those blood vessels are significantly damaged by atherosclerosis, diabetes, or other vascular disease, the supply of nitric oxide is reduced at its source. The pills can only boost what is already there; they cannot create it from nothing.⁶

The penile arteries are among the smallest in the body, so they tend to show the effects of vascular damage earlier than larger vessels like the coronary arteries. Erectile dysfunction that does not respond well to medication can be an early warning sign of broader cardiovascular problems, sometimes appearing years before a heart attack or stroke would.⁷ This is one reason your doctor may want to investigate further rather than simply moving to a stronger treatment. Getting a vascular workup is not just about your erections; it could reveal risk factors that matter for your life.

Penile Injections

For men who genuinely do not respond to oral medications, self-injected medications directly into the penis are the most established second-line therapy. The idea sounds alarming, but the needles are very fine (similar to insulin syringes), and most men who try it report that the discomfort is minimal once they learn proper technique. The most widely used formulation is trimix, a combination of three drugs that together produce an erection by relaxing smooth muscle and increasing blood flow through pathways that do not depend on nitric oxide the way pills do.

Effectiveness is high. About 89% of men using trimix were able to have intercourse, including men with serious comorbidities like diabetes and prior pelvic radiation, though response rates were somewhat lower in those groups.⁸ Across the published literature, clinical efficacy ranges from roughly 54 to 100% depending on the formulation and population studied.⁹ The risk of priapism, an erection that will not go down and requires emergency treatment, was extremely low at 0.5% in one large review.⁸

The main problem with injections is not effectiveness but sticking with them. Discontinuation rates can reach 38% within a few years, driven by the inconvenience of injecting before sex and the loss of spontaneity.⁹ Careful counseling about what to expect, and sometimes adjusting the dose over several visits, makes a real difference in whether men continue with this option long-term.¹⁰

Urethral Pellets as a Needle-Free Alternative

If the thought of injecting yourself is a dealbreaker, there is a middle ground. MUSE (medicated urethral system for erection) is a tiny pellet of alprostadil inserted into the urethra through the tip of the penis using a slim applicator. The drug is absorbed through the urethral lining and produces an erection through the same direct smooth-muscle relaxation as an injection, just with a less invasive delivery method.

In a study specifically of men whose erectile dysfunction was refractory to PDE5 inhibitors, about 68% responded to MUSE.¹¹ The success rate varies by underlying cause, with men who had radical prostatectomy responding at somewhat lower rates (around 58% in that study) compared to men with high blood pressure alone (74%). The most common side effect is a burning sensation in the urethra, reported by about 29% of users, but serious complications like priapism or infection are essentially absent.¹² Many men prefer MUSE over injections because of its simplicity, even though injections tend to produce firmer erections on average.¹³

Vacuum Erection Devices

A vacuum erection device (VED) is a plastic cylinder that fits over the penis and uses negative pressure to draw blood into the erectile tissue. Once the erection is established, a constriction band is placed at the base to maintain it. The technology is decades old, requires no drugs, and works regardless of the underlying cause of erectile dysfunction.

A recent meta-analysis pooling data across multiple studies found that the overall efficacy of VEDs was about 80%, with success rates varying by cause: roughly 83% for mixed causes, 73% for diabetes, 72% for spinal cord injury, and about 85% after radical prostatectomy.¹⁴ The most common complaint is bruising, occurring in about a quarter of users. Erections produced by a VED feel different from natural ones. The penis tends to be cooler and may pivot at the base rather than standing firmly, which some couples find awkward at first. The constriction ring should not be left on for more than 30 minutes.

VEDs are also used in penile rehabilitation programs after prostate surgery, where regular use helps maintain blood flow and tissue oxygenation during the months when natural erections are recovering.¹⁵ They are inexpensive compared to ongoing medication costs and have essentially no systemic side effects, which makes them a sensible option for men on complex medication regimens or those who prefer to avoid drugs entirely.

Low-Intensity Shockwave Therapy

Low-intensity extracorporeal shockwave therapy (Li-ESWT) is a newer approach that aims to treat the root cause of vascular erectile dysfunction rather than just managing symptoms. The device delivers acoustic waves to the penile tissue, which in theory stimulates new blood vessel growth and improves endothelial function. Unlike injections or pills, the goal is to produce lasting improvement in natural erectile function.

In a double-blind, sham-controlled trial of men who were PDE5 inhibitor non-responders, about half were able to achieve erections firm enough for penetration with PDE5 inhibitors after receiving shockwave therapy, compared to the sham group that did not improve.¹⁶ A multicenter trial reported that about 68% of PDE5 inhibitor non-responders achieved erections sufficient for intercourse after combined shockwave therapy and medication, with significant improvements in blood flow on ultrasound testing.¹⁷

The treatment is not permanent for everyone. At 18-month follow-up in one study, about 64% of men still had a satisfactory sexual life, though most of them needed to continue using oral medication alongside the shockwave benefit. Younger men with shorter duration of erectile dysfunction and moderate rather than severe disease responded best.¹⁸ Shockwave therapy is appealing because it has virtually no side effects and targets the underlying vascular problem, but it works best when there is still some residual vascular function to build on. In severe, long-standing cases, it is less likely to be sufficient.

The Role of Psychology and Relationships

Not all erectile difficulty is plumbing. Performance anxiety, depression, relationship conflict, and the stress of previous failures can all interfere with erections in ways that no pill or injection fully addresses. In younger men especially, nonorganic causes account for a significant share of erectile dysfunction, and these causes respond to different interventions.

A pilot study comparing cognitive behavioral sex therapy (CBST) to sildenafil in men with psychogenic erectile dysfunction found that the therapy was comparably effective at improving erectile function scores, and it outperformed the drug in reducing anxiety.¹⁹ Another study found that combining CBST with sildenafil produced faster clinical success than sildenafil alone, with men reaching their goals earlier in the treatment window.²⁰

Partners matter too. Erectile dysfunction has detrimental effects on both the man and his sexual partner, and physicians are increasingly encouraged to treat it as a shared health concern rather than an individual one.²¹ When a partner feels excluded from the treatment process, or when the pressure to “perform” replaces intimacy, medications can fail even when the blood flow is there. If your erectile difficulty has a psychological component, and most cases involve at least some psychological overlay, ignoring it means leaving one of your best treatment levers untouched.

Exercise and Lifestyle Changes

Exercise is sometimes dismissed as a soft recommendation, something doctors say because they are supposed to. But the evidence for physical activity improving erectile function is concrete and operates through several distinct mechanisms: it improves blood vessel function and nitric oxide production, lowers blood pressure, improves insulin sensitivity, and boosts testosterone levels.²² Exercise also appears to have a synergistic effect with PDE5 inhibitors, meaning it can make the pills work better in men who have a partial response.

Weight loss in obese men, reducing alcohol intake, quitting smoking, and managing blood sugar in diabetes have all shown measurable improvements in erectile function in clinical trials.²³ These changes address the same vascular and hormonal mechanisms that cause erectile dysfunction in the first place. No one is suggesting that a jog will replace a penile implant in a man with severe vascular disease, but for the large number of men whose erectile dysfunction is driven by metabolic syndrome, obesity, or sedentary lifestyle, these modifications can genuinely shift the needle and sometimes restore function that pills alone could not.

Penile Implants

When other treatments have failed or are impractical, a penile prosthesis is the definitive surgical option. The most common type is the inflatable penile prosthesis (IPP), which consists of two cylinders placed inside the penis, a small pump placed in the scrotum, and a fluid reservoir. Squeezing the pump transfers fluid into the cylinders, producing a rigid erection on demand. Deflating it returns the penis to a natural-looking flaccid state.

Satisfaction rates with implants are consistently among the highest of any erectile dysfunction treatment. In a 20-year follow-up study, men who were still using their device reported high quality of life scores across functional, relational, personal, and social domains.²⁴ The catch is durability: about half of the devices in that study experienced some complication over 20 years, with mechanical failure being the most common. The estimated device survival at 20 years was 53%, and 41% of patients were still using the original device at that point. These numbers mean that a younger man receiving an implant should expect revision surgery at some point during his lifetime.

Infection rates with modern antibiotic-coated devices have been driven down substantially, ranging from under 1% to about 5% depending on the study and patient population.²⁵ An infected implant must be removed, which is a setback but can usually be managed with a salvage procedure. Despite the surgical nature of the treatment, most men and their partners who commit to an implant report being glad they did, and many wish they had not waited so long.

Vascular Stenting for Erectile Dysfunction

In cases where erectile dysfunction is caused by a specific blockage in the internal pudendal arteries, an approach borrowed from cardiology is being explored: placing tiny stents to reopen the narrowed vessels. A feasibility study using drug-eluting stents in the pudendal arteries of men with a poor response to PDE5 inhibitors found that the procedure was feasible and associated with meaningful improvements in both subjective and objective measures of erectile function.²⁶ Research with bioabsorbable stents, which dissolve after the vessel has healed, showed a restenosis rate of 30% for shorter lesions.²⁷

This is still an emerging field. The available data comes from small trials, and pudendal artery stenting is not widely offered or included in standard guidelines. It represents a possible future option for a very specific subset of men with focal arterial blockages, not a current mainstream treatment. But for men whose erectile dysfunction has a clear arterial cause identified on imaging, it is a space worth watching.

Stem Cells and Platelet-Rich Plasma

Regenerative therapies are the frontier of erectile dysfunction treatment. Stem cell injections into the erectile tissue aim to restore damaged smooth muscle and endothelial cells rather than bypassing them. Early clinical trials have shown encouraging improvements in erectile function scores with an acceptable safety profile, but the field is still in its early stages. Larger and more rigorous trials are needed before anyone can recommend stem cell therapy as a standard treatment, and the optimal dosing, timing, and delivery methods remain unknown.²⁸

Platelet-rich plasma (PRP), sometimes marketed as the “P-shot,” involves concentrating growth factors from your own blood and injecting them into penile tissue. The first randomized, placebo-controlled trials have shown promising results with no significant adverse events.²⁹ The caution here is that PRP is already being aggressively marketed by clinics despite the evidence being preliminary. If you encounter a clinic offering PRP as a proven cure, that is getting ahead of the science. The early results are genuinely interesting, but “interesting early results” is a long way from “established treatment.” Be wary of paying premium prices for something still under investigation.

Mapping Out a Reasonable Treatment Pathway

When you step back and look at the full range of options, the treatment pathway for erectile dysfunction has a logic to it. Oral medications and lifestyle changes are the least invasive and cheapest starting point, and they deserve a genuine trial with proper technique. If they are not working, checking for and treating low testosterone is a simple next step that can rescue an otherwise failed response to pills. Shockwave therapy sits in a similar space, potentially restoring enough vascular function to make oral medications effective again. Injections and urethral pellets represent a step up in commitment and invasiveness but offer high success rates even in difficult cases. Vacuum devices are an underappreciated option at any stage. Penile implants are the end of the line, and they work reliably, but they are irreversible in the sense that the natural erectile tissue is permanently altered by the surgery.

The costs associated with switching from one failed treatment to another add up, and research has long emphasized that getting the initial treatment right matters more than having a long list of fallbacks.³⁰ That means honest, thorough evaluation up front. A man whose erectile dysfunction is primarily psychological will not be well served by years of escalating medical treatments. A man with severe vascular disease and low testosterone is unlikely to respond to pills alone no matter how many times he tries. Matching the treatment to the actual cause, rather than working through a generic checklist, is how you avoid wasting time and money on approaches that were never likely to work for you.