We show how Schwitzer inequality allows us to find inequalities relating an additive descriptor of the form \( D_p(G)=\sum_{i=1}^N c_i^p \) to its reciprocal \( D_{-p}(G)=\sum_{i=1}^N c_i^{-p} \). We look at three cases (the inverse degree, the Kirchhoff, and the multiplicative degree-Kirchhoff indices) where \( p=1 \) and where, of the two \( D_1(G) \) and \( D_{-1}(G) \), one is known in closed form, therefore allowing to find an upper bounds for the other.