  We explore possible effects of a magnetar burst on the radio, X-ray, and
gamma-ray flux of a pulsar wind nebula (PWN). We assume that the burst injects
electron-positron pairs or powers the magnetic field and explore the total
energy at injection and the spectral index needed in order to increase the
X-ray flux by about one order of magnitude, as well as its decay time until
reaching quiescence. We also explore magnetically powered phenomenology that
could explain a temporary increase of the PWN synchrotron emitted flux and
perhaps the relatively common lack of PWNe surrounding magnetars. This
phenomenological study is of interest for fast radio bursts (FRBs) as well,
given that the connection between magnetars and this kind of systems have been
recently established observationally.
