Simultaneous recordings of the pattern visual evoked potential and the pattern electroretinogram were recorded in a case of unilateral optic neuritis following a bee sting on the eye. The patient presented with severe eye pain, apoplectic visual loss, acute optic disc swelling and minimal signs of ocular inflammation and eyelid edema. The vision failed to recover. The electrophysiological recordings initially showed a delay in the P100 wave of the pattern visual evoked potential. On follow-up, a normal latency and amplitude of the P50 wave of the pattern electroretinogram was recorded with the flattening of the N95 component, but the pattern visual evoked potential was absent. The data suggests that the optic nerve was demyelinated acutely, and that subsequently axonal loss and degeneration of retinal ganglion cells occurred.