The paper deals with a nonlocal problem related to the equilibrium of a confined plasma in a Tokamak machine. This problem involves terms $u_{*}^{\text{'}}\left(\right|u>u\left(x\right)\left|\right)$ and $|u>u(x\left)\right|$, which are neither local, nor continuous, nor monotone. By using the Galerkin approximate method and establishing some properties of the decreasing rearrangement, we prove the existence of solutions to such problem.