A simple supplement could improve Long Covid symptoms

Are you willing to participate in a simple long covid trial? All about bypassing the tryptophan absorption system in the intestine.

If the intestine is struggling to absorb tryptophan, could taking 5HTP be an alternative option for creating serotonin?

Miller, H. E. J., J. F. W. Deakin, and I. M. Anderson. "Effect of acute tryptophan depletion on CO2-induced anxiety in patients with panic disorder and normal volunteers." The British Journal of Psychiatry 176.2 (2000): 182-188.

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If tryptophan uptake was abrogated by poly(I:C) treatment, tryptophan supplementation should elevate serotonin levels even during viral inflammation. To corroborate this, we used a diet containing a glycine-tryptophan dipeptide, which bypasses the need for B⁰AT1 and enables tryptophan uptake via dipeptide transporters.

This diet compensated for impaired uptake in poly(I:C)-treated mice and led to an increase in both tryptophan and serotonin levels in systemic circulation (Figures 5H and 5I). Similarly, supplementation with the serotonin precursor 5-hydroxytryptophan (5-HTP), which bypasses the requirement for tryptophan, rescued serotonin levels in poly(I:C)-injected mice (Figure 5J). Collectively, these data demonstrate that viral-RNA-induced inflammation impairs intestinal tryptophan uptake, which causes systemic serotonin depletion.
Wong, Andrea C., et al. "Serotonin reduction in post-acute sequelae of viral infection." Cell (2023).

Happy to hear your thoughts.