I am a 74-year old man with ED who enjoys sex. I do get erections sometimes, but they are soft. I was told to do the injections, but I don’t feel that is the answer. I am in very excellent health. I walk 4 miles a day, have a lot of energy, and look 10 years younger. My medications are:

  • Aggrenox: 25 mg (aspirin)/200 mg (dipyridamole)
  • Amlodipine besylate: 10 mg
  • Simvastatin: 10 mg

I need your help. Please give me some advice about the supplements I can take that would help my erection problem. It is driving me crazy.

JOE, Bellmore NY

Dear Joe,

Your question is not uncommon in men our age. Causes of ED are usually due to some degree of neurogenic, atherosclerotic or hormonal deficiency, or a combination. Although you indicated that you were in excellent health, it appears from your medications that you are being treated for several cardiovascular risk factors: hypertension (for which you are taking Amlodipine—a calcium channel blocker), hyperlipidemia (treated with Simvastatin), and risk for blood clots (the usual reason for taking Aggrenox, a combination of aspirin and dipyridimole [Persantine]—both platelet aggregation inhibitors).

Before initiating treatment for ED, we need to consider reversible causes, including potential side effects of your medications.

I don’t think there’s a problem with Aggrenox, but there may be questions about Amlodipine or Simvastatin. Although Amlodipine rarely causes ED, if you do an Internet search of “Amlodipine AND ED OR Erectile Dysfunction,” a number of anecdotal reports will pop up.

Likewise, the statin drugs aren’t commonly associated with ED, but a growing number of reports are emerging which indicate that Simvastatin and other statins may be a cause of ED.1–3 The best way to determine whether a drug is causing your ED would be to discontinue the medication for several weeks to see if there is any improvement—and then to “rechallenge” yourself with the medication to see if the problem recurs. Of course, make sure you discuss this with your physician before making any changes.

While you’re at it, I suggest you ask your physician to check your testosterone levels. If they are in the low or low-normal range, you might ask him to prescribe testosterone. I prefer injectable testosterone (cypionate or enanthate), usually 200 mg injected intramuscularly every 2–3 weeks. Alternatively, the topical creams or gels may also help, although I believe topical testosterone is not as effective as the injectable route.

Another approach in this regard, is Life Enhancement’s Tribulus Desire, which contains the herb, Tribulus terrestris, designed to naturally increase your testosterone. In a study conducted in Bulgaria, a Tribulus extract was given to eight apparently healthy men, ages 28–45, in a dose of 250 mg three times per day for five days. The testosterone levels increased, on average, threefold.4

There are several nutritional alternatives to Viagra and the other phosphodiesterase (PDE-5)-inhibiting drugs like Cialis and Levitra, all of which are designed to increase the production of endothelium-derived nitric oxide (NO), one of the most important signaling molecules in our bodies. Nitric oxide was designated “Molecule of the Year” by the journal Science in 1992, and a Nobel Prize in Physiology or Medicine was awarded in 1998 for its discovery. Unfortunately as we age, we lose our ability to produce NO. This puts us at risk for a host of conditions, including hypertension, atherosclerosis, myocardial infarction (i.e., heart attacks), stroke, Alzheimer’s disease, and erectile dysfunction.

One way to increase NO is to consume the nitric oxide-producing amino acid, arginine.The effect of oral arginine intake to improve erectile response was first investigated in animal models. Older rats supplemented with arginine demonstrated increased nitric oxide synthase activity and increased nitric oxide levels, which caused improved erectile response. The authors suggested dietary supplementation with arginine might lead to improved sexual performance in humans, as well.5

The first published evidence that oral supplementation with arginine might improve human sexual function came from a short-term study in 1994.6 The study showed a positive correlation between arginine supplementation and sexual performance and satisfaction.

These intriguing findings were supported by a more recent, larger study conducted at the Department of Urology and Nephrology at Tel Aviv University in Israel. Fifty men with confirmed erectile dysfunction were administered either a placebo or 5 g/day arginine for six weeks. Thirty-one percent of the subjects receiving arginine reported improvement and satisfaction in their sexual performance. In the placebo group, only 12% of the men noted improvement in sexual function.7 The percentage of patients reporting improved performance (31%) may not sound like an impressive number, but keep in mind that up to 50% of Viagra users report no benefit from taking this expensive prescription medication.

As one source of arginine, I suggest Life Enhancement’s ProSexual Plus, which offers a hefty 3000 mg of L-arginine per serving.

Fig. 1. The Urea Cycle. In this metabolic pathway, arginine is catalyzed by the enzyme arginase to urea and ornithine. Ornithine, in turn, is converted to citrulline, which is converted to argininosuccinate, which is converted back to arginine, completing the cycle.
(click on thumbnail for full sized image)


Unfortunately, the intestinal enzyme, arginasereduces the effectiveness of the conversion of oral arginine to NO by metabolizing arginine, reducing the amount that is available for conversion to NO. Citrulline may offer a solution. Citrulline is a semi-essential amino acid that is not found in the diet—it is synthesized in the body via a mechanism called the urea cycle (Fig. 1). It has recently been shown that oral citrulline supplementation increases the plasma arginine concentration and augments NO- dependent signaling in a dose-dependent manner. This provides the rationale for using oral citrulline supplementation as a donor for the arginine/NO pathway in those with ED.


In a study in the journal Urology, researchers tested the efficacy and safety of oral citrulline to improve erection hardness in patients with mild ED.8 In this study, 24 men with mild ED [erection hardness score (EHS) of 3] received a placebo for 1 month, followed by citrulline, at 1.5 g/day split into two doses, for another month. At the end of the study, 12 (50%) of the 24 men reported achieving an EHS of 4 (an EHS of 3 is considered “hard enough for penetration but not completely hard,” while an EHS 4 is “completely hard and fully rigid”). Thus, citrulline increased hardness by 50%. In addition, citrulline increased successful intercourse connects by 56% more than placebo, and all patients whose EHS improved from 3 to 4 reported being “very satisfied.” Life Enhancement’s Inner Power contains 500 mg of citrulline per serving.

Perhaps the most effective way to increase nitric oxide has recently become available. It is a patent-pending combination of natural products, developed at the University of Texas Health Science Center, in Houston, Texas, called Neo-40.9 Neo-40 is primarily a combination of nitrate-rich beet root, and nitrate reductase activity-enhancing Hawthorn Berry extract, plus a relatively small amount of citrulline.

Preliminary clinical studies at the Houston Institute for Clinical Research indicate that Neo-40 has demonstrated clinically relevant increases in NO and serum nitrate concentration, improvement in triglyceride levels, and normalization of blood pressure in hypertensive patients. Anecdotal reports from my patients who have used Neo-40 also include rapid relief from angina attacks, and Viagra-like enhancement of sexual performance.

Another approach to improving erectile dysfunction is the time-honored multi-purpose herb Ginkgo biloba extract (GBE). In a 1991 study, fifty patients with proven arterial erectile impotence were treated with 240 mg of GBE daily for nine months.10 The patients were divided into two groups. The first group had achieved sufficient erections with intracavernous papaverine injections before beginning treatment with GBE. The second group had not achieved sufficient erections with high-dose papaverine injections.

In the first group (n = 20), all patients regained spontaneous and sufficient erections after six months of oral GBE treatment. Arterial flow rates were actually improved after three months and continued to improve at six months. Rigidities at the penile tip and base were significantly improved after six months and remained constant during the nine month duration of the study.

In the second group (n = 30) (this was the group that did not respond to high-dose papaverine injections—i.e., a very severe state of ED), improved arterial penile flow rates and rigidities were noted at six and nine months. Nineteen patients, responded to intracavernous PGE1 following GBE treatment. Of these 19 patients, 9 required a minimal dose of 5 mcg PGE1, while the other 11 required a maximal dose of 20 mcg. The remaining 11 patients remained impotent.

Thus, it appears that Ginkgo biloba extract at a dose of 240 mg per day may also greatly assist those with ED.

I would be remiss if I did not include the time-honored, traditional aphrodisiac, Korean Red Ginseng. Although this herb has been honored for thousands of years, scientists continue to study its properties, generally confirming its libido and performance-enhancing properties.11 For example, in a double-blind, placebo-controlled study, 45 men with moderate to severe erectile dysfunction had found improvement in their scores on erectile performance and sexual satisfaction after treated with three times daily doses of 900 mg Korean red ginseng for 8 weeks.12 A similar study on 60 men with erectile dysfunction also reported marked improvement in erectile function including rigidity, penetration, and maintenance of erection after taking Korean red ginseng (1000 mg) three times daily for 12 weeks.13

In summary, I recommend evaluation of testosterone levels, and replacement, if appropriate, or using Tribulus Desire. Arginine (3–5 gm per day) and Citrulline (1.5 gm per day), Ginkgo biloba (240 mg per day), Red Ginseng (as in RedGidity) 900–1000 mg per day. I don’t recommend starting everything at one time—rather, begin with one nutrient at a time, and add other nutrients in sequence so you can tell what is (and is not) working.

Ward Dean, M.D.


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9. Sohn M and R. Sikora. Ginkgo biloba extract in the therapy of erectile dysfunction. J Sex Educ Ther. (1991) 17: 53-61. 
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