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Over-the-Counter Nitric Oxide for ED: Does It Work?


  • Over-the-counter nitric oxide supplements may help with ED and offer other benefits.
  • Viagra and its active component sildenafil help the body produce more nitric oxide to improve blood flow to the penis.
  • Doctors have found that OTC nitric oxide supplements improve the effects of tadalafil.
  • Nitric oxide supplement ingredients like L-arginine and L-citrulline produce few side effects. 

Nitric oxide is the magic behind Viagra. Sildenafil, the active ingredient in Viagra, works by enhancing the action of nitric oxide on blood vessels, increasing blood flow to the penis (and throughout the body). Because Viagra works through the nitric oxide pathway, over-the-counter nitric oxide supplements may achieve similar effects. Can these OTC nitric oxide supplements improve your erections? 

What Are Over-the-counter Nitric Oxide Supplements?

You may find over-the-counter nitric oxide supplements online and get the impression that these products contain nitric oxide that your body can readily put to use. However, over-the-counter nitric oxide products do not contain nitric oxide. They contain ingredients that help your body produce more nitric oxide. It is impractical — and may be impossible — to include nitric oxide in a supplement. 

What Is Nitric Oxide?

Nitric oxide (NO) is a colorless gas with a sharp odor. It is also known as nitrogen oxide or nitrogen monoxide. Do not confuse it with nitrogen dioxide (NO2) or nitrous oxide (N2O). The former is a pollutant, and the latter an anesthetic, often called laughing gas. 

From a biological perspective, nitric oxide is a messenger molecule that plays a role in many biological processes. Its lifetime is only a few seconds or less. It crosses membranes easily, however, performing its messaging and signaling duties almost instantly. 

Where Nitric Oxide Originates

The body synthesizes nitric oxide from substances like L-arginine and L-citrulline. It uses specialized enzymes to derive nitric oxide from these compounds. Over-the-counter nitric oxide supplements contain ingredients like L-arginine and L-citrulline. By making these available to the body in significant amounts, they may cause more nitric oxide to form. 

How Viagra Uses Nitric Oxide to Help Erections

Viagra does not contain nitric oxide. Its active compound is sildenafil, a phosphodiesterase 5 inhibitor. By inhibiting this substance, sildenafil stimulates the body to produce more nitric oxide. 

The inner lining of the blood vessels uses nitric oxide to send a message to the surrounding smooth muscles to relax. When the muscles relax, the blood vessels dilate, allowing more blood to pass through. This effect can reduce blood pressure and enhance your erections. 

The Health Benefits of Nitric Oxide Supplements

Nitric oxide is an essential biological messenger molecule. Physical exercise enhances its production in the muscles. By providing more raw materials for nitric oxide production, over-the-counter nitric oxide supplements may help the body make more NO. 

Nitric Oxide Supplements May Play a Role in Muscular “Pumps”

Physical exercise increases NO production in muscles. And NO relaxes smooth muscles, allowing blood vessels to dilate and let more blood through. Therefore, NO may play a role in the muscular “pumps” you get when working out. 

Nitric oxide may help your “pumps.”

Fit man working out
Nitric oxide may help your “pumps.”

Some people take over-the-counter nitric oxide supplements to help them work out more and recover faster following workouts.

Researchers have found that citrulline malate, an ingredient in some nitric oxide supplements, enhances anaerobic muscle performance and shortens recovery times. The compound may significantly reduce muscle soreness. 

Increased blood flow to the muscles may hasten the delivery of essential nutrients and the evacuation of by-products that cause muscle soreness. 

OTC Nitric Oxide May Help Achieve and Maintain Erections

By improving blood flow to the penis, nitric oxide supplements may help trigger erections and maintain them longer, enhancing sexual performance. 

Although scientific evidence is scant in this respect, some research suggests that quality over-the-counter nitric oxide supplements may help drugs like Viagra and Cialis achieve better results. L-arginine is the compound that may be responsible for these effects. 

L-citrulline may also help boost erections and sexual performance, but it’s not as effective as sildenafil or tadalafil. 

Nitric Oxide Supplements May Help with High Blood Pressure

High blood pressure, one of the conditions that make up metabolic syndrome, occurs when the circulating blood exerts high pressure on the walls of blood vessels. By allowing the blood vessels to dilate, NO creates more space for blood to flow through. Thus, it reduces the pressure that blood flow exerts on the blood vessel walls. 

Researchers have noted that people with high blood pressure may be unable to generate enough nitric oxide. This impaired nitric oxide production reduces the flexibility of blood vessels and arteries, causing high blood pressure. 

OTC nitric oxide may help such people regain blood vessel flexibility and improve their blood pressure. 

Nitric Oxide Supplements May Help Manage Type 2 Diabetes

The links between nitric oxide and type 2 diabetes aren’t clear. Researchers have found, however, that diabetes patients don’t produce as much nitric oxide as healthy people. They don’t know whether impaired NO production contributes to diabetes or is a result of diabetes. 

We know that diabetes damages blood vessels, causing high blood pressure over time. And NO production may be a factor in that equation.

Researchers already suspect that nitric oxide supplements can improve NO production in diabetes patients. They also know that L-arginine supplementation can fight diabetes

L-arginine may even delay the progression of the disease. However, we need more research to prove the suspected links between NO and diabetes. 

Other Benefits of Nitric Oxide Supplementation

People attribute many other anecdotal benefits to NO supplements, like: 

  • Enhancing the healing of diabetic lesions
  • Helping with weight loss
  • Fighting the common cold
  • Improving trauma recovery
  • Reducing the symptoms of altitude sickness

The Risks and Side Effects of Over-the-counter Nitric Oxide Supplements

People generally tolerate over-the-counter nitric oxide supplements well. Whether you take nitric oxide for ED or other conditions, you should know that it can have some side effects. 

Compounds like L-arginine may cause an upset stomach, nausea, headaches, palpitations, and heartburn. Some of the side effects of these supplements may be more severe. 

Man in pain sitting on the bed

Low Blood Pressure

By relaxing the blood vessels and dilating them, nitric oxide lowers blood pressure. Those with high blood pressure may welcome this effect. But those whose blood pressure is already low won’t appreciate having it lowered further. 

Liver Cirrhosis

Nitric oxide supplements containing compounds like L-arginine and L-citrulline may hurt liver function. Those who already suffer from cirrhosis or other liver problems should avoid these supplements. 

Higher Chance of Death After a Heart Attack

While in general, NO supplements have cardiovascular benefits, taking them after a heart attack may make matters worse, according to the Mayo Clinic. Patients who take L-arginine post heart attack may be at higher risk for repeat heart attacks and death. 

eDrugstore Can Help

The available evidence indicates that boosting nitric oxide for ED may make sense. NO supplements that include L-arginine may boost the effects of FDA-approved ED solutions like Viagra and Cialis. In addition to these lifestyle medications, we also carry over-the-counter nitric oxide. Unlike FDA-approved drugs, nitric oxide supplements do not require a prescription.

When you order with eDrugstore, telehealth visits and shipping are always free.

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