Thanks for the well-curated set of links!
Background
The tl;dr version of the links above is that men with PE "often have high histamine levels." And, histamine in known to play an important role in orgasm and ejaculation.
The essential amino acid L-Histidine is converted into histamine by the body. So the theory is that taking L-Histidine supplements may make it easier to orgasm, presumably by raising histamine levels. Since L-Histidine is an essential amino acid and naturally present in many foods, reasonable amounts of supplementation should be fairly safe.
Based on the above, I did a little more research. I was not able to find any clinical studies about the effect of L-Histidine on sexual function in general or delayed ejaculation specifically. There were several recent review articles on treatment for delayed ejaculation, but they all focused on off-label use of prescription medications. The reviews’ conclusions were generally that delayed ejaculation hasn’t been studied very much, and most of the attempted treatments so far have not been conclusively shown to have measurable effects.
I have found several mentions (in blogs and discussion forums) of one study by Dr. Carl Pfeiffer, in his book "Mental and Elemental Nutrients" (1975). Reportedly, in this study anorgasmic women were given 1.5g of L-Histidine supplements per day, and reported some (unquantified) restoration of sexual function. I wasn’t able to read the book, and although many studies cite the book (Google Scholar), none of those studies relate to sexual function.
One frequently expressed concern for L-Histidine supplementation is that Histamine, of course, is also linked to allergic reactions. Personally, I’m allergic to pollen, cats, dust, etc. So I’m a bit cautious about this. However, others have pointed out that L-Histidine is actually supposed to improve Histamine balance/regulation in the body. And several forum posters (and posters on Amazon.com) have claimed that L-Histidine supplementation actually improved or even stopped their allergies. On the flip side, if the goal is to achieve premature ejaculation, making your Histamine levels MORE regulated is presumably NOT what one would want. :-)
Method
So this is somewhat uncharted territory, but I’m going to give it a shot! I’ve ordered a couple of bottles of Swanson brand L-Histidine capsules (https://www.ama … /dp/B0026R59VK/ ) and they’ll arrive today. I plan to start with one 500mg capsule three times per day (so a total of 1.5g per day, similar to the reported Pfeiffer study) and see what happens. Depending on the effect, I may vary this by raising the amount, or try taking the whole dose at once a few hours before sex.
Assessment
Unlike PE goals, it will be hard to quantify this. My base goal is a threshold goal: in the past, I have never been able to orgasm through oral sex alone. If, after taking this supplement for a few days, I orgasm through oral sex, I’ll view it as a reasonable hypothesis that the supplement was related.
Another interest of mine has been to achieve the "hands-free" orgasm, I.e., not touching the penis at all and achieving erection and then orgasm. I have never been able to do that. So if I can do that after starting this supplement, that will be another data point.
Finally, I’ll subjectively track ease of orgasm when masturbating and see if it becomes subjectively easier to orgasm, if my refractory period decreases, etc. Those will be more subjective assessments, of course.
I’ll post updates in a week or so. If anyone else has ideas for other supplements, please do share!
