Protocol · Men's Health
Erectile Dysfunction Protocol
L-Citrulline and Panax Ginseng (Korean Red Ginseng) are the core of this stack, with 5 supporting supplements. Each row gives the amount the protocol lists and the grade our evidence database holds for that supplement in Erectile Dysfunction.
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
7 supplements · 4 graded · 4 confirmed studies
| Grade | Supplement | Amount listed | Why it’s in the stack | Evidence on file | Shop |
|---|---|---|---|---|---|
| Primary stackThe core of this protocol | |||||
| L-Citrulline | Amount listed: 1.5–3 g daily | Converted to arginine, increasing nitric oxide production and improving blood flow to erectile tissue
| Not graded yet | ||
Confirmed studies for L-Citrulline (titles as PubMed lists them) | |||||
| Panax Ginseng (Korean Red Ginseng) | Amount listed: 900–1,800 mg daily | Ginsenosides enhance nitric oxide release and relax smooth muscle in erectile tissue
| Not graded yet | ||
| Supporting stackListed as additions to the core | |||||
| L-Carnitine/Propionyl-L-Carnitine | Amount listed: 2 g daily (propionyl-L-carnitine preferred) | Improves energy metabolism in penile tissue; propionyl-L-carnitine may enhance PDE5 inhibitor response
| Grade B for Erections2 studies · 147 people | ||
| Maca Root | Amount listed: 1.5–3 g daily | Adaptogen that improves sexual desire and may enhance erectile function through non-hormonal mechanisms
| Grade C for Erections50 people | ||
| Tribulus Terrestris | Amount listed: 250–750 mg daily | May support testosterone levels and enhance libido; traditional use for sexual dysfunction
| Grade C for Blood Pressure180 people | ||
Confirmed studies for Tribulus Terrestris (titles as PubMed lists them) | |||||
| Pycnogenol | Amount listed: 40–120 mg daily | Pine bark extract that enhances endothelial nitric oxide production; often combined with L-arginine | Not graded yet | ||
Confirmed studies for Pycnogenol (titles as PubMed lists them) | |||||
| Saffron | Amount listed: 30 mg daily | May improve erectile function and sexual satisfaction; especially studied in SSRI-induced dysfunction
| Grade C for Depression Symptoms18 studies · 30 people | ||
Confirmed studies for Saffron (titles as PubMed lists them) | |||||
Shop the evidence-backed picks
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Or shop one supplement
The supplement in this protocol graded A or B. Each opens third-party tested products, matched to the dose above where we can.
- Grade B
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How this protocol works
In plain language
Erectile dysfunction (ED) is the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. It affects about 50% of men over 40 to some degree and becomes more common with age. ED is primarily a vascular condition—erections depend on adequate blood flow. Nitric oxide (NO) is the key molecule that relaxes blood vessels and allows blood to fill the erectile tissue. ED can also be an early warning sign of cardiovascular disease.
IMPORTANT: ED can signal underlying cardiovascular disease, diabetes, or hormonal problems. See a healthcare provider for evaluation. PDE5 inhibitors (Viagra, Cialis) remain the most effective treatment for most men.
- L-Citrulline is an amino acid that's converted to arginine in the body, which then produces nitric oxide—the molecule that relaxes blood vessels and enables erections. Citrulline is actually more effective at raising blood arginine levels than taking arginine directly. Studies show over 50% of men with mild ED report improvement.
- Panax Ginseng (Korean Red Ginseng) is the most evidence-backed herb for ED. Its active compounds (ginsenosides) enhance nitric oxide production and relax the smooth muscle in erectile tissue. Multiple meta-analyses confirm it significantly improves erectile function scores.
- L-Carnitine/Propionyl-L-Carnitine supports energy metabolism in penile tissue. Propionyl-L-carnitine specifically may enhance the response to PDE5 inhibitors (like Viagra) in men who don't respond well to medication alone. It addresses metabolic aspects of erectile function.
- Maca Root is a Peruvian plant that has been used for centuries for sexual function. Research shows it improves sexual desire and may help with mild erectile dysfunction. Interestingly, it doesn't appear to work by changing hormone levels, suggesting it acts through other mechanisms.
- Tribulus Terrestris is a traditional herb used for male sexual health. While claims about dramatically boosting testosterone are overstated, studies suggest it may modestly improve erectile function and libido in men with mild to moderate ED.
- Pycnogenol (pine bark extract) enhances nitric oxide production from the endothelium (blood vessel lining). When combined with L-arginine, studies show impressive results—up to 92% of men achieved normal erections in one trial.
- Saffron may be particularly helpful for antidepressant-induced sexual dysfunction. SSRIs commonly cause erectile problems, and saffron has shown benefit in this specific population. It may also help with libido and satisfaction.
Expected timeline: L-citrulline/Pycnogenol: days to weeks. Ginseng: 2-4 weeks. Maca/Tribulus: 4-8 weeks. Lifestyle factors (exercise, weight loss, not smoking) are also important.