The most effective option for staying hard is a prescription oral medication, commonly known as an ED pill. These work for the majority of men and take effect within an hour. Beyond prescriptions, certain supplements, lifestyle changes, and hormonal factors can also play a role, especially for mild difficulties or as part of a longer-term strategy.
Prescription ED Medications
Oral ED medications are the most reliable and well-studied treatment. They all work the same way: relaxing blood vessels in the penis so blood flows in more easily and stays there. The main differences come down to how fast they kick in and how long they last.
Sildenafil (Viagra) has a half-life of about 4 hours, meaning it’s most effective within that window. The typical starting dose is taken roughly one hour before sex. Vardenafil (Levitra) is nearly 10 times more potent at a biochemical level, so lower doses are used, which can mean fewer side effects. Its half-life runs 4 to 6 hours. Tadalafil (Cialis) is the longest-lasting option with a half-life of 17.5 hours, which lets you take it well ahead of time without needing to closely time sex around the pill.
One practical detail that matters: a heavy or high-fat meal delays absorption of sildenafil by about an hour and can make it less effective. If you plan to eat beforehand, keep it light or eat earlier in the day to give your body time to digest. Tadalafil is less affected by food.
These medications are not safe to combine with nitrate-based heart medications like nitroglycerin patches or isosorbide tablets. The combination causes large, sudden drops in blood pressure and can reduce blood flow to the heart itself. Studies published in the journal Circulation documented that this interaction can create a dangerous cycle of falling blood pressure and cardiac ischemia. If you take any form of nitrate, these pills are off the table.
Supplements That Have Some Evidence
If you’re looking for something available without a prescription, a few supplements have at least preliminary clinical support, though none come close to the effectiveness of ED medications.
L-citrulline is an amino acid your body converts into L-arginine, which then helps produce nitric oxide, the molecule that relaxes blood vessels and enables erections. A clinical trial tested 1.5 grams daily for one month in men with mild ED and found improvements in erection hardness compared to placebo, though the study was small (24 men). Effective doses in broader use typically range from 3 to 6 grams daily. L-citrulline is generally preferred over taking L-arginine directly because it survives digestion better and produces a more sustained increase in the body.
L-arginine taken on its own, at doses of 3 to 5 grams daily, has also shown statistically significant improvements in mild to moderate ED across meta-analyses. Higher doses tend to be needed compared to citrulline.
Korean red ginseng has the strongest herbal evidence. In a double-blind crossover study published in The Journal of Urology, men taking 900 mg three times daily saw meaningful improvements in erectile function scores, and 60% reported that ginseng improved their erections. That’s a real effect, but keep expectations realistic: ginseng is a support tool, not a replacement for medication in moderate or severe cases.
Lifestyle Factors That Affect Hardness
Erections are fundamentally a cardiovascular event. Anything that improves blood vessel health tends to improve erectile quality over time. Regular aerobic exercise, maintaining a healthy weight, and managing blood pressure all have a direct impact on how well blood flows into the penis.
Beetroot juice has gained attention because it’s rich in dietary nitrates, which your body converts into nitric oxide. One cup daily has been shown to lower blood pressure as effectively as some medications. That said, there are no clinical studies directly testing beetroot juice for ED. The vascular benefits are real, but treating it as a targeted erection fix goes beyond what the evidence supports.
Smoking is one of the fastest ways to damage the blood vessels that erections depend on. Excessive alcohol acts as a depressant that interferes with arousal signals. Poor sleep and chronic stress both suppress testosterone production. These aren’t dramatic revelations, but they’re often the root cause when younger, otherwise healthy men notice their erections aren’t as firm as they used to be.
When Testosterone Is the Problem
Low testosterone can contribute to weaker erections, though it’s more commonly associated with low desire than with the physical mechanics of staying hard. The American Urological Association defines low testosterone as a total level below 300 ng/dL and recommends testing in all men who present with erectile difficulties.
If your levels are below that threshold, testosterone replacement therapy may help, though the response is variable. Some men see clear improvement in erectile function, while others don’t. Low testosterone is more likely to be a factor if you’re also experiencing fatigue, reduced sex drive, loss of muscle mass, or mood changes alongside erection problems.
Zinc and Micronutrient Deficiencies
Zinc plays a role in testosterone production, and a genuine deficiency can drag levels down enough to affect sexual function. The recommended daily intake for adult men is 11 mg, with an upper safe limit of 40 mg. If you eat a varied diet with meat, shellfish, or legumes, you’re probably getting enough. Supplementing beyond what your body needs won’t boost testosterone or improve erections. Zinc only helps if you’re actually deficient, which a simple blood test can confirm.
What to Avoid: OTC “Male Enhancement” Products
Gas station pills, convenience store supplements, and online products marketed as natural male enhancement are a genuine safety risk. The FDA maintains an active database of hundreds of these products found to contain hidden pharmaceutical ingredients, often the same active compounds found in prescription ED medications but at uncontrolled doses. These products are sometimes falsely marketed as dietary supplements or all-natural treatments. Because the actual ingredients aren’t listed, you have no way to know what you’re taking, how much is in each pill, or whether it will interact dangerously with other medications. The FDA has stated plainly that these products “can lead to severe health issues and hospitalization.”
Choosing the Right Approach
Current urology guidelines don’t require you to start with the least invasive option and work your way up. The American Urological Association explicitly states that any treatment is a valid first choice, and recommends that clinicians discuss all options, from oral medications to more advanced treatments, so you can make an informed decision based on your own priorities.
For most men, an oral ED medication is the fastest and most effective starting point. Supplements like L-citrulline and Korean red ginseng are reasonable additions, especially for mild cases or if you prefer to try something over the counter first. Lifestyle changes work on a longer timeline but address the underlying vascular health that erections depend on. And if low libido is part of the picture, getting your testosterone checked is worth doing early in the process rather than as an afterthought.