Protocol · Men's Health
Male Sexual Dysfunction (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 Male Sexual Dysfunction (Erectile Dysfunction).
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
7 supplements · 3 graded · 3 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 (or 6–8 g citrulline malate) | Increases arginine and nitric oxide production, 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 Korean red ginseng daily | Ginsenosides enhance nitric oxide release, improve smooth muscle relaxation, and support testosterone
| Grade B for Erections4 studies · 195 people | ||
| Supporting stackListed as additions to the core | |||||
| Maca Root | Amount listed: 1.5–3 g daily | Adaptogen that improves sexual desire and may enhance erectile function independent of hormones
| Grade C for Estrogen1 study · 56 people | ||
Confirmed studies for Maca Root (titles as PubMed lists them) | |||||
| Pycnogenol | Amount listed: 40–120 mg daily (often combined with L-arginine) | Pine bark extract that enhances endothelial nitric oxide production and blood flow
| Not graded yet | ||
Confirmed studies for Pycnogenol (titles as PubMed lists them) | |||||
| Tongkat Ali (Longjack) | Amount listed: 200–400 mg standardized extract daily | May increase testosterone and reduce cortisol, improving libido and erectile function | Not graded yet | ||
| Fenugreek | Amount listed: 500–600 mg standardized extract daily | Contains furostanolic saponins that may support testosterone and enhance libido
| Grade C for Libido60 people | ||
| Zinc | Amount listed: 15–30 mg daily (if deficient) | Essential for testosterone production; deficiency impairs sexual function | Not graded yet | ||
Shop the evidence-backed picks
The collection holds the supplements we grade A or B for its theme, in third-party tested products where the catalog has them. It opens in our Fullscript store. You can look through it without signing in; Fullscript asks for a free account to order.
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) affects up to 50% of men over 40 to some degree. While it can have psychological components, ED is often a vascular issue—erections depend on adequate blood flow. In fact, ED can be an early warning sign of cardiovascular disease. This protocol supports erectile function through improving blood flow and supporting healthy testosterone levels.
IMPORTANT: ED can signal underlying cardiovascular disease, diabetes, or hormonal issues. Get evaluated by a healthcare provider before relying solely on supplements.
- L-Citrulline is converted to arginine in the body, which then produces nitric oxide (NO)—the key molecule that relaxes blood vessel walls and allows increased blood flow to the penis. Citrulline is actually more effective at raising arginine levels than taking arginine directly (which is poorly absorbed). One study found that over 50% of men with mild ED reported improvement after taking citrulline.
- Panax Ginseng (Korean Red Ginseng) is the most studied herb for ED with consistently positive results. Its ginsenosides enhance nitric oxide release in erectile tissue, relax smooth muscle, and may support testosterone. Multiple meta-analyses support its effectiveness, with improvements in erectile function scores comparable to some pharmaceutical treatments.
- Maca Root is a Peruvian plant that has been used for centuries to enhance fertility and libido. Research shows it improves sexual desire and may help erectile function, interestingly without directly affecting testosterone levels—suggesting it works through other mechanisms, possibly affecting neurotransmitters.
- Pycnogenol (pine bark extract) enhances nitric oxide production by the endothelium (blood vessel lining). Studies combining Pycnogenol with L-arginine show significant improvements in erectile function, with up to 92% of participants achieving normal erections in one trial.
- Tongkat Ali (Eurycoma longifolia) may help by supporting healthy testosterone levels and reducing stress hormones (cortisol). It's particularly useful when low testosterone or high stress contributes to dysfunction.
- Fenugreek contains compounds that may support testosterone levels and enhance libido. Studies show improvements in sexual function and satisfaction.
- Zinc is essential for testosterone production. Many men are mildly deficient, and correcting this can improve testosterone levels and sexual function. Don't exceed recommended doses long-term.
Expected timeline: Citrulline and Pycnogenol may show effects within days to weeks. Ginseng: 2-4 weeks. Maca and Tongkat Ali: 4-8 weeks for full effects. Address cardiovascular health for long-term improvement.