I had a series of blood test prescribed by my Allergy/Immunologist Dr which confirmed not only my sensitivity to pollens, dust mites and pets, but also a long list of fragrance and food colorant, and very low immunity against Tetanus, Diphtheria and Pertussis and Pneumonia. So I got the DTP and pneumonia vaccines. However, regarding all the rashes and recurring sinus infection there was no particular recommendation other than to try to identify and avoid food, detergents, soaps containing fragrances. I showed the DO all the lab results and he suggested to try to apply nicotine patches because they would improve the immune system. His suggestion certainly worked for me and I am thankful for it.

If you have the time for it, you may want to enter into Google Search "using nicotine patches to improve immunity" and read only those that are not linked to any commercial purposes!
Here are two links about the subject:
https://pubmed.ncbi.nlm.nih.gov/36650574/
https://www.verywellhealth.com/nicotine-patches-long-covid-treatment-8705089