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Clinical Studies

Irexis ingredients are backed by published Clinical Studies for sexual function, desire and libido. Here are the amazing results discovered:
  • Increased sexual function – “increased sexual behavior of males” [1]
  • Greater Sperm Production – “increased sperm count”  [2]
  • A Decrease in Erectile Problems
  • Increased Sexual Desire
  • Strengthened Erections [3]

How Irexis Was Developed:

Interest in medicinal plants to treat sexual dysfunctions has increased in the last 20 years. The ingredients resulting in the proprietary formula for Irexis male enhancement pills have been studied for years and shown to benefit sexual function.  Featured ingredients in Irexis male enhancement pills are backed with clinical studies:

L-arginine has been clinically proven to raise nitric oxide levels triggering added blood flow to the penis and improved erections. (European Urology, June 2002)

Korean red ginseng, or Panax Ginseng, has vast clinical support (7 human clinical studies) proving its efficacy for male sexual function and health.

Irexis male sex pills are formulated only with ingredients backed by over 40 years of research. Irexis contains only the safest ingredients that have been meticulously selected for quality and purity. Purchase with confidence, Irexis is 100% backed by our money back guarantee.

Clinical Studies:

Understanding natural herbs and medicinal plants and their role in health and disease has been the concern of scientists and researchers for decades. Collective research study highlights for prosexual ingredients and the understanding of their fundamental benefits are referenced below.


Study Highlights:

A systematic review has been performed on effect of maca on sexual function in humans. In this review, according to the authors only four randomized clinical trials (RCT) met all the inclusion criteria.

A further RCT assessed the effects of maca in patients with mild erectile dysfunction using the International Index of Erectile Dysfunction-5 and showed significant effects on subjective perception of general and sexual well-being.

In a study in 9 apparently healthy men who had received maca for 4 months showed an increase in seminal volume, sperm count, and sperm motility.

Based on exceedingly preliminary evidence, the herb maca (Lepidium meyenii) has been advertised as "herbal Viagra." In one study in rats, use of maca enhanced male sexual function. There is one published human trial as well. In this small, 12-week, double-blind, placebo-controlled study, use of maca at 1,500 mg or 3,000 mg increased male libido.

Maca (Lepidium meyenii) may boost sexual desire in men, according to one study. Maca has been grown as a vegetable in Peru for thousands of years. Source: University of Maryland Medical Center

A Peruvian randomized, double blind study, showed Maca improved subjective evaluation of sexual desire in 57 men treated with 1.5g or 3.0g maca for 12 weeks compared to placebo.

Lepidium meyenii (Maca) is a cultivated root belonging to the brassica family used in the Andean region for its presumed aphrodisiac properties. A double-blind clinical trial on 50 Caucasian men concerned  with mild erectile dysfunction (ED), randomised to treatment with Maca dry extract, 2400 mg, or placebo. The study concluded a small but significant effect of Maca supplementation on subjective perception of general and sexual well-being in adult patients with mild ED.


Study Highlights:

A 26-week, double-blind, placebo-controlled trial compared the effects of treatment with zinc (66 mg of zinc sulfate, supplying 15 mg of zinc), folate (5 mg), and zinc plus folate against placebo. A total of 108 fertile men and 103 men with impaired fertility (“subfertile men”) participated in the study. The two supplements combined significantly improved the sperm count and the percentage of healthy sperm in the subfertile men; neither supplement alone produced this effect, and there was little effect of the combined therapy on fertile men.

Severe zinc deficiency is known to negatively affect sexual function. Since marginal zinc deficiency is relatively common, it is logical to suppose that supplementation with zinc may be helpful for some men. However, this hypothesis has only been studied in men receiving kidney dialysis. The results were promising.

Korean Red Ginseng

Study Highlights:

Two double-blind, placebo-controlled trials, involving a total of about 135 people, have found evidence that Korean red ginseng may improve erectile function.

In the better of the two trials, 45 participants received either placebo or Korean red ginseng at a dose of 900 mg 3 times daily for 8 weeks. After a 1-week period of no treatment, the two groups were switched. The results indicate that while using Korean red ginseng men experienced significantly better sexual function than while they were taking placebo.

Korean red ginseng (Panax ginseng) helped men with ED improve sexual function, according to one double-blind study. People in the study took 2 weeks off after 8 weeks of treatment.  Source: University of Maryland Medical Center

Some men use Panax ginseng on the skin of the penis as part of a multi-ingredient product for treating early orgasm (premature ejaculation). Men also use it for erectile dysfunction (ED). There is some evidence that Panax ginseng is effective for these uses.

Male impotence (erectile dysfunction, ED). Taking Panax ginseng by mouth seems to improve sexual function in men with ED.

The Department of Urology, University of Ulsan College of Medicine, Asan Medical Center and Korea Ginseng and Tobacco Research Institute, Seoul, Korea - The group receiving ginseng, changes in early detumescence and erectile parameters such as penile rigidity and girth, libido and patient satisfactions were significantly higher than that of other groups. The administration of Korean red ginseng has shown to have superior effects compared to the placebo or trazodone.

Effects of ginseng: involvement of nitric oxide study: 107 active or inactive chemical entities obtained from the roots, leaves, and flower buds of various ginseng species,  categorized as: saponins, polysaccharides, polyynes, flavonoids, and volatile oils. Only saponins show bioactivities. Generally, ginseng has a good safety record. The common adaptogenic ginsengs (Panax ginseng and Panax quinquefolia) are commonly considered to be rather safe even in large amounts. For most people, ginseng tastes sweet and is well tolerated. The latest studies enrich the understanding of aphrodisiac effect, cardiovascular effect, neuropharmacological effect of ginseng.

Ginkgo Biloba   

Study Highlights:

Ginkgo (Ginkgo biloba) increases circulation and may improve sexual function, although one study found no effect. Ginkgo may increase the effects of certain blood-thinning medications (anticoagulants), so ask your doctor before taking ginkgo. University of Maryland Medical Center.

In regard to decreased libido and erectile dysfunction - it has been postulated that Ginkgo may be effective for treating erectile dysfunction. Ginkgo may help dilate blood vessels.


Study Highlights:

The substance nitric oxide (NO) plays a role developing an erection. Drugs such as Viagra work to increase the body's response to the natural increase of NO that develops with sexual stimulation. A straightforward approach might be to increase NO levels, and one potential way to accomplish this encompasses use of the amino acid L-arginine. Oral arginine supplements are thought to increase nitric oxide levels in the body including the penis. Based on this, L-arginine has been publicized as "natural Viagra."

Oat Straw

Study Highlights:

Oat straw, advocated as a stop-smoking treatment, also used to enhance sexual function. One double-blind, placebo-controlled study of 75 men and women indicated finding that use of an oat straw product enhanced the sexual experience for men, but not for women.

It has been asserted that oat straw works by increasing the amount of free testosterone in the blood. Many marketers of oat straw state that, with advancing age, testosterone in the body tends to become bound up and inactivated, leading to numerous problems including weakening sexual function, and that oat straw potentially reverses this process.

In one study, 40% of men in the treatment group (L-arginine) reported improvement, compared to none in the placebo group.

In another study, 50 men with confirmed ED were administered  5g L-arginine a day or matching placebo for six weeks. 31% of patients taking the L-arginine reported significant subjective improvement in sexual function.

Catuaba Bark Extract

Study Highlights:

Catuaba is used to heighten sexual arousal and treat male sexual performance problems. [http://www.webmd.com/ CATUABA]

In Brazil, a herbal medicinal extract named Catuama containing a mixture of Paullinia cupana (guarana; Sapindaceae), Trichilia catigua (catuaba; Meliaceae), Ptychopetalum olacoides (muirapuama; Olacaceae) and Zingiber officinale (ginger; Zingiberaceae) is used as a body stimulant, energetic, tonic and aphrodisiac.

The most famous of all Brazilian aphrodisiac plants, Catuaba has been valued for generations. The Tupi Indians first discovered the qualities of the plant for its function as a stimulant of the nervous system, as well as for its ability to strengthen erections.

Back in 1992, researchers in Japan found catuaba extracts (species Erythroxylum catuaba) to have potential antibacterial and anti-HIV activity. Catuaba, when given to mice, protected them from E. Coli and Staph infections/ Catuaba was also able to prevent the HIV virus from attaching to cells, and, in addition, catuaba prevented the death of white blood cells exposed to the HIV virus.

An October 2007 study published in "Planta Medica" investigated the effects of 14 commercial samples of catuaba on the corpus cavernosum, which is the erectile tissue of the penis, using rabbits.

Tribulus Terrestris

Study Highlights:

An Indonesian study at Airlangga University, Indonesia and National University of Singapore 6th Biennial Asian-Pacific Meeting on Impotence in Kuala Lumpur, Malaysia (1997) analyzed Tribulus terrestris L (TTL) an herbal plant native to Bulgaria and China with a vast history as a powerful aphrodisiac and used as a traditional medicine for treating male infertility. A chemical compound isolated from TTL named protodioscin has been identified, purified and standardized as a phytochemical agent. The study concludes that protodioscin in TTL is possibly the precursor of DHEA in patients with a low serum level of the hormone. Results of the study showed: TTL improved sex drive in 60% of the ED cases. Since this improvement in sex function is complemented by an improvement in the DHEA levels, the study surmises that improvement in the sex drive of these patients is linked to the conversion of protodioscin, the active ingredient of the TTL extract, into DHEA-S.


Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice.

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