I've never done a master cleanse, but after 4 liver flushes, my allergies are somewhat better. They have been really severe in the last couple of years, and they are not too bad this spriing, though I still have to take all my meds. I also have been getting accupuncture, which has helped my sinus headaches in the past.

You may want to consider looking at some candida information. What it is and the symptoms.