Does /sci/ know of any natural/non-prescription immunosuppressants? e.g. supplements, plants, herbs, etc. that can be easily obtained to suppress the immune system.

Ciclosporin would be an example of an immunosuppressant derived from a natural fungi, but it requires processing to produce.

Triptolide naturally produced by the 'thunder god vine' (tripterygium wilfordii) is a good example, but unfortunately the plant has a high level of toxicity.

https://en.wikipedia.org/wiki/Tripterygium_wilfordii

All recommendations are welcome.