What Can a Man Take to Help Erectile Dysfunction?

Phosphodiesterase type 5 (PDE5) inhibitors, the drug class that includes sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra), are the most widely prescribed and studied treatments for erectile dysfunction. They work for a majority of men regardless of whether the cause is vascular disease, diabetes, surgery, or psychological factors. But pills are far from the only option. Depending on what is driving the problem, the range of effective treatments extends from amino acid supplements and dietary changes to injectable medications, hormone therapy, and mechanical devices.

How Erection Medications Actually Work

An erection depends on the relaxation of smooth muscle inside the penis. When a man is sexually aroused, nerve and blood-vessel cells in the erectile tissue release nitric oxide, a signaling molecule that triggers production of a substance called cGMP. That cGMP is what tells the smooth muscle to relax, allowing blood to rush in and produce firmness.¹ The body also produces an enzyme, PDE5, whose job is to break cGMP down and end the erection. In men with ED, that balance tips too far toward breakdown. PDE5 inhibitors block the enzyme, letting cGMP accumulate and the erection persist.² This is why the pills require sexual arousal to work; they amplify an existing signal rather than creating one from scratch.

Choosing Between Sildenafil, Tadalafil, and Other PDE5 Inhibitors

All PDE5 inhibitors share the same core mechanism, but they differ in how long they last and how patients experience them. Sildenafil and vardenafil are shorter-acting, typically taken 30 to 60 minutes before sex, with effects lasting roughly four to six hours. Tadalafil lasts much longer, up to 36 hours in some men, which is why it earned the nickname “the weekend pill.”

A large analysis of patient-reported outcomes from over 130,000 men found that sildenafil at medium and high doses produced better scores for satisfaction, hardness, and maintenance of erection compared with similar doses of tadalafil when both were used on demand.³ That doesn’t mean sildenafil is categorically “better.” Tadalafil can also be taken as a low daily dose rather than on demand, and a randomized trial found that daily tadalafil was superior to on-demand sildenafil for improving erectile function and penetration success, while also reducing symptoms of depression and anxiety.⁴ Pooled data from tadalafil’s clinical-trial database confirm that both the daily and on-demand regimens produce significant improvements across different patient subgroups.⁵

In practice, the choice often comes down to lifestyle. Men who prefer spontaneity tend to gravitate toward daily tadalafil because they don’t have to plan around a pill. Men who have sex less frequently, or who want the most intense on-demand response, often start with sildenafil. Side effects overlap across the class and include headache, flushing, nasal congestion, and occasionally visual disturbances with sildenafil. Back pain and muscle aches are more common with tadalafil. Most men try one and switch if it doesn’t suit them.

When Oral Medications Don’t Work

PDE5 inhibitors fail for a meaningful minority of men, especially those with diabetes. Erectile dysfunction is a common complication of diabetes, and roughly half of diabetic men develop it within a few years of diagnosis. The underlying nerve and blood-vessel damage from elevated blood sugar disrupts the molecular pathways that these pills depend on, so response rates are lower than in the general population.⁶

For men who don’t respond to pills, alprostadil is the most established next step. This synthetic version of prostaglandin E1 relaxes smooth muscle directly, bypassing the nitric-oxide pathway entirely.⁷ It can be delivered two ways. A small pellet inserted into the urethra (the MUSE system) is less invasive, and in clinical trials about two-thirds of men who responded during office testing went on to have successful intercourse at home.⁸ The other route is intracavernosal injection, where a man uses a fine needle to inject medication directly into the side of the penis. This sounds worse than it is; the needle is very small, and most men report the discomfort as minimal after the first few tries.

Injectable formulations sometimes combine multiple drugs. Papaverine relaxes smooth muscle by raising cGMP and cAMP levels inside cells, while phentolamine blocks the nerve signals that keep blood vessels constricted. Together, these two drugs produce stronger relaxation than either alone.⁹ A common “triple mix” adds alprostadil to the combination. Injections have high success rates even in men with severe vascular ED, but they carry a risk of priapism (a prolonged erection that requires emergency treatment), so proper dosing and medical supervision are essential.

Testosterone Replacement

Low testosterone is not the most common cause of ED, but when levels are genuinely low, it can be a significant contributor. A meta-analysis of trials involving men with confirmed low testosterone found that supplementation improved erections in about 65% of treated men, compared with roughly 17% on placebo.¹⁰ Testosterone can be delivered through gels, patches, or injections.

The catch is that testosterone replacement only helps if you are genuinely deficient. A blood test confirming low levels, ideally drawn in the morning when testosterone peaks, is essential before starting treatment. Men with normal testosterone who take supplemental hormones are unlikely to see erectile improvement and face risks including elevated red blood cell counts, potential cardiovascular concerns, and suppressed sperm production. Some clinicians also combine testosterone with a PDE5 inhibitor in hypogonadal men who don’t respond adequately to either alone.

Supplements With Some Evidence Behind Them

The supplement market for ED is enormous and mostly unregulated, but a handful of compounds have at least preliminary clinical data supporting them. The strength of that evidence varies considerably.

L-Citrulline

L-citrulline is an amino acid found in watermelon and other foods. The body converts it into L-arginine, which is the raw material for nitric oxide production, the same pathway that PDE5 inhibitors rely on. L-citrulline has an advantage over taking L-arginine directly because arginine is heavily broken down in the gut before it reaches the bloodstream, while citrulline survives that process and is converted to arginine later.¹¹ In a small trial, citrulline supplementation improved erection hardness in men with mild ED. The effect is modest compared with prescription drugs, but for men with borderline issues or those looking to support vascular health alongside other treatments, it’s a reasonable option with a good safety profile. One trial also found that adding L-arginine to sildenafil produced better results than sildenafil alone, suggesting the two pathways can complement each other.¹²

Red Ginseng

Korean red ginseng (Panax ginseng) is one of the most studied herbal remedies for ED. An early trial found a 60% overall improvement rate in the ginseng group compared with 30% for placebo, with benefits in rigidity, libido, and satisfaction.¹³ A systematic review pooling six randomized trials also found a significant benefit, with treated men roughly 2.4 times more likely to report improvement.¹⁴ However, a more recent Cochrane review applied stricter criteria and concluded the actual effect on standardized erectile-function scores was “trivial,” with low confidence in the evidence overall.¹⁵ The honest reading is that ginseng probably produces some benefit, but it is small and the research quality is not strong enough to know exactly how much.

Yohimbine

Yohimbine, derived from the bark of the African yohimbe tree, was one of the first pharmacological treatments for ED, predating PDE5 inhibitors. It works through a different mechanism, blocking alpha-2 adrenergic receptors that normally inhibit erection. A meta-analysis found that yohimbine alone roughly doubled the odds of improvement compared with placebo, and combining it with other agents increased those odds further.¹⁶ Side effects can include anxiety, rapid heart rate, and elevated blood pressure, which limits its usefulness in men with cardiovascular conditions. Prescription yohimbine (as yohimbine hydrochloride) is standardized, but over-the-counter yohimbe bark extracts vary wildly in potency, making dosing unpredictable.

Icariin (Horny Goat Weed)

Epimedium, commonly sold as “horny goat weed,” contains a flavonoid called icariin that acts as a natural PDE5 inhibitor.¹⁷ Lab studies confirm that icariin and its chemical relatives can inhibit the same enzyme targeted by sildenafil.¹⁸ The problem is that icariin is far less potent than prescription PDE5 inhibitors, and the amount of active compound in a supplement capsule is poorly standardized. Researchers continue investigating modified versions of icariin that could be more effective, but as of now, no rigorous clinical trial has demonstrated that swallowing a horny goat weed supplement produces meaningful erectile improvement in humans.¹⁹

Diet, Exercise, and Pelvic Floor Training

ED is closely linked to cardiovascular health. The arteries supplying the penis are smaller than those feeding the heart, so the same atherosclerotic process that leads to heart disease often shows up as ED first. That connection means lifestyle interventions aimed at the heart also help erections.

A Mediterranean-style eating pattern, rich in olive oil, vegetables, fruits, whole grains, nuts, and fish, has been associated with lower risk and severity of ED, particularly in men with type 2 diabetes. The benefits likely stem from improved blood-sugar and cholesterol metabolism, increased antioxidant protection, and higher arginine intake, which feeds nitric oxide production.²⁰

Aerobic exercise has consistent evidence behind it as well. Regular cardio improves endothelial function, the ability of blood vessel walls to dilate on cue, which is exactly the process that falters in vascular ED. Even moderate increases in physical activity have been linked to measurable improvements in erectile function scores.

Pelvic floor exercises are an underappreciated option. A randomized trial assigned men with ED to pelvic floor muscle training with biofeedback or to a control group. After three months, the exercise group showed significantly better erectile function scores. By six months, 40% of participants had regained normal erectile function, another 35% had improved, and only about a quarter saw no benefit.²¹ These exercises strengthen the muscles at the base of the penis that help trap blood during an erection. They are free, carry no side effects, and can be combined with any other treatment.

Vacuum Devices and Shockwave Therapy

A vacuum erection device (VED) is a plastic cylinder that fits over the penis and uses a hand pump to create negative pressure, drawing blood into the erectile tissue. Once an erection forms, a constriction ring slides to the base of the penis to maintain it. VEDs are particularly common after radical prostatectomy for prostate cancer, where nerve damage makes pharmaceutical options less reliable. Beyond producing erections on demand, regular use of a VED is thought to improve blood flow and oxygenation to the penile tissue, potentially supporting long-term recovery of natural function.²² The devices are effective regardless of the cause of ED but produce erections that feel different from natural ones; the penis can be cooler to the touch and pivot at the base rather than standing rigid from the body.

Low-intensity extracorporeal shockwave therapy (LI-ESWT) is a newer approach that applies acoustic pulses to the penile tissue. The idea is that these tiny shockwaves create microscopic trauma that stimulates the growth of new blood vessels.²³ Early trials showed promising results, and it’s the only treatment that aims to fix the underlying blood supply rather than work around it. That said, the evidence is still mixed. Protocols vary from clinic to clinic, there is no consensus on the ideal number of sessions, energy settings, or treatment intervals, and some well-designed trials have failed to show a benefit. Many urology guidelines still consider it experimental.

PDE5 Inhibitors Work for Psychological ED Too

A common misconception is that if ED is “in your head,” medication won’t help. In reality, PDE5 inhibitors are effective for psychogenic ED and for mixed cases where both psychological and physical factors are at play. A trial of sildenafil in men with psychogenic or mixed ED found significant improvements in erection frequency, hardness, duration, and overall satisfaction compared with placebo.²⁴ The reason is straightforward: performance anxiety creates a feedback loop. A man worries about losing his erection, the anxiety triggers adrenaline, adrenaline constricts blood vessels, and the erection fails, confirming the worry. PDE5 inhibitors disrupt that loop by providing a pharmacological floor of support. Many men find that after a few successful encounters with medication, the anxiety dissipates and they can eventually reduce or stop the pills.

The Nitrate Warning and Other Safety Concerns

The single most dangerous interaction with PDE5 inhibitors involves nitrate medications, which include nitroglycerin (taken for chest pain), isosorbide mononitrate, and isosorbide dinitrate. Both nitrates and PDE5 inhibitors lower blood pressure through overlapping pathways, and combining them can cause a severe, prolonged drop in blood pressure that reduces blood flow to the heart and brain.²⁵ This interaction applies to all PDE5 inhibitors, including tadalafil despite its longer window of action.²⁶ The combination has caused deaths. It’s not a matter of caution; it is an absolute rule: if you take any form of nitrate, PDE5 inhibitors are off the table.²⁷

Recreational use of “poppers” (amyl nitrite, butyl nitrite) carries the same risk. These are nitric oxide donors and behave like prescription nitrates in the body. Alpha-blockers, used for enlarged prostate or high blood pressure, can also interact with PDE5 inhibitors and cause dizziness or fainting, though the interaction is manageable with dose adjustments and timing.

The Hidden Danger of Over-the-Counter “Male Enhancement” Products

Walk into a gas station or browse online marketplaces and you’ll find shelves of supplements promising to fix ED with “all-natural” ingredients. The reality is grimmer than the packaging suggests. An analysis of 91 supplements marketed as natural sexual enhancers found that 81% contained undeclared pharmaceutical PDE5 inhibitors, including sildenafil and tadalafil. Nearly a fifth of those contained more than 110% of the highest approved prescription dose.²⁸ Others contained unregulated chemical analogs of these drugs, compounds with similar structures but no human safety data.

This is not a minor labeling issue. A man taking what he believes is a harmless herbal pill could be ingesting an unpredictable dose of the same drug his doctor would have prescribed with medical oversight, but without warnings about nitrate interactions, without dosing guidance, and potentially laced with contaminants.²⁹ Counterfeit versions of branded PDE5 inhibitors sold through unregulated online pharmacies carry similar risks, with tablets that may contain too much active ingredient, too little, or harmful fillers.³⁰ If you want to try a PDE5 inhibitor, get it from a licensed pharmacy with a prescription. The generic versions of sildenafil and tadalafil are inexpensive now that patents have expired, so the economic argument for buying unregulated alternatives has largely evaporated.

Matching the Treatment to the Cause

ED is a symptom, not a single disease, and the right treatment depends on what is driving it. For most men, especially those over 40, the cause is predominantly vascular: the blood vessels that fill the penis have stiffened or narrowed. PDE5 inhibitors are the standard first step here, and diet, exercise, and cardiovascular risk management form the long-term foundation.

For men who’ve had prostate surgery, the issue is often nerve damage. Recovery can take a year or more, and a rehabilitation strategy that combines PDE5 inhibitors, vacuum devices, and sometimes injections gives the tissue the best chance of regaining function over time. For men with low testosterone confirmed by blood work, hormone replacement addresses a root cause rather than just a symptom. And for men whose ED is primarily psychological, a combination of short-term PDE5 inhibitor use and therapy, especially cognitive behavioral approaches targeting performance anxiety, tends to produce lasting results.

The worst strategy is to do nothing. ED tends to be progressive when the underlying cause is left untreated, and because it shares risk factors with heart disease and diabetes, it can serve as an early warning that those conditions need attention. Bringing it up with a doctor is the most effective single step a man can take, and it opens the door to treatments that have been studied in trials involving hundreds of thousands of patients. The options are broader and more effective than most men realize.