When a dynamic system to be analyzed is subjected to velocity-dependent force(s), a quadratic eigenproblem arises. This paper presents an efficient algorithm for the calculation of the eigensolutions' sensitivity in quadratic eigenproblems, the attention being focused on how to extract eigenvalue and eigenvector derivatives of a general non-defective eigenpair directly in the configuration space. The method preserves the banded nature of the structural matrices and requires knowledge of only the eigenvectors to be differentiated, which makes it powerful in dealing with large scale systems.