hi, thanks for writing to us.
Monteleukast and levocitrizine are not the cause, so do not worry.
the treatment followed by you is fine , it takes time and seasonal variation for the eczema
to reduce in severity.
till that time avoid any cosmetics for the body, avoid the use of detergents for washing his clothes, avoid using any natural products for his skin.
use only gentle neutral ph soaps, and the rest of the treatment as you have been giving.
thank you regards.