Aw, I can hear how frustrated you are, and totoo naman na sobrang lala ng atopic dermatitis lalo na sa ganitong edad. Honestly, a month in pa lang kayo kaya normal na hindi pa fully cleared ang skin niya, my friend's baby had the same thing and it took like 2-3 months before makita talaga ang major improvement, so don't lose hope! One thing na simukhang nakatulong sa kanya is strict moisture barrier, yung parang i-apply agad after bath habang wet pa ang skin para ma-lock in ang moisture, tapos Cetaphil or Aveeno baby lotion (hypoallergenic ang hinahanap talaga namin), and also check niyo if the Mustela products are working okay or if kailangan mag-switch pa to something lighter or more gentle. Since you're already doing most of the right things (NAN HA, antihistamine, fragrance-free products, gentle detergent), I'd say mag-check back with your pedia soon if it's not improving, or maybe ask for a referral to a dermatologist para may second opinion, sometimes kailangan ng different approach or prescription strength creams. You're doing great though, mama, I promise this phase passes!