A quick update of my case: since approximately three months, the intensity of my POIS decreased significantly. Especially the permanent symptoms I was suffering from, which are much less violent and even perceptible (I had tachycardia absolutely all the time until April, in particular, and now much less and only in the hours following arousal). If I abstain from arousal for more than a day, I feel almost normal after the night, and showers systematically erase my post-arousal symptoms. As for the post-orgasmic symptoms, they're still there, but well controlled with Paracetamol, and they disappear after a day or two.
So this is for the "hard" symptoms, but I still do not feel like before my POIS become "permanent": I never feel perfectly healthy, physically or psychologically, and just a little arousal is enough to trigger the usual symptoms again. (There are often different symptoms according to the time, not the complete set each time: sometimes chills, sometimes pelvic pain, sometimes need to sleep, loss of appetite... though always nervousness, mood shift, weakness.)
What I've done concretely since April:
1/ stop taking Omega-3 (they were beneficial in the beginning, they calmed tachycardia, nervous and anxiety-related symptoms, but I felt that some other POIS problems were increased after a few months, like strange issues when falling asleep, and they ceased immediately after stopping Omega-3 ; and they were less efficient in the long run, tachycardia had returned after weeks or months and I was feeling generally unwell) ;
2/ taking artichoke+rosemary pills daily for 2 months, which are supposed to be good for the intestines and liver, and have choleretic properties: gut problems decreased markedly (no more constipation, although it returns if I stop the pills), I don't know if it's linked to the rest of the symptoms decrease ;
3/ eating more eggs, approximately every two days. (EDIT: + I also stopped milk and ate much less cheese.)
So I don't know precisely why, but after a few weeks, in May, I was really better and I still am. No change since then.
Next envisaged steps: I believe that I'll try a supplementation of amino acids to see if it changes anything, and I shall probably look for a few other blood tests (B1, B3, cortisol, ACTH come to my mind as for now). I may also see a gastroenterologist.
