Hi and thanks for asking us on HCM. You have been treated heavily with antibiotics, antifungals and even antivirals - all these can undermine your immune system, making you more sensitive to the environment. Other factors that can suppress or disturb the immune system include sudden weight changes, stress, steroids and hormonal dysfunction. You are in your 40 s, of normal weight - unless you have had a significant infection in the past that could have lead to immunodeficiency, I do not see the need to test for it. You could do a baseline blood test (full blood count, liver and kidney function) just to make sure all is well after taking so much medication. I suggest trying to rebuild your immune defense. Start taking fish oil generously (2 - 4 capsules daily), vitamin C with zinc, probiotics and antioxidants to start with. Be sure to stick to a nutritious diet rich in lean protein, vegetables and fruits. Hydrate and sleep well and do exercise regularly if you aren t already doing so. Where the hives are concerned, you could take a short course of antihistamines. Soaking in oatmeal and applying a pre-colled moisturizer can greatly help with symptoms. Use gentle skin cleansers and do not rub at your body with a rough towel after bath. Use soft towels and dab gently. I hope this helps Thank you