Metaplectic-c quantization was developed by Robinson and Rawnsley as an
alternative to the classical Kostant-Souriau quantization procedure with half-form
correction. Given a metaplectic-c quantizable symplectic manifold and a real-valued function on that manifold, we propose a condition under which a regular value of the function is a quantized energy level for the system. We discuss the properties of this condition, and we determine the quantized energy levels of the harmonic oscillator and the hydrogen atom.