Magnetic monopole Lagrangian and Hamiltonian

How do I find an equation analogous to
begin{equation}
mathcal{L}(q,dot q)=frac12 m dot q ^2-qphi+qvec{dot q}cdot vec Aquadquad text{where}quad vec B =vecnablatimesvec A, quad vec E=-vecnablaphi-partial_tvec A
end{equation}
for magnetic monopole instead of the electric point charge coupling to the $A$-field?