I was diagnosed with seborrheic dermatitis 3 years ago and no solution has worked so far. The prescribed medicated shampoos suppress it, but, only if I'm using them every alternate day. If I stop shampooing even for 2 days, it flares up again. This has caused lot of hairloss and greying of hair. I'm now switching to using dry shampoo like reetha and bhringraj powder, apple cider vinegar and curd with lemon. They're having same effect like shampoo for suppressing it. I have started using probiotic supplement tablet with 30billlion mcu. How long should I take this supplement to make my gut healthy and reduce this skin infection?