  This work calculates the first correction to the leading order q\={q}
dilepton production rates due to shear viscosity in an expanding gas. The
modified rates are integrated over the space-time history of a viscous
hydrodynamic simulation of RHIC collisions. The net result is a {\em hardening}
of $q_\perp$ spectrum with the magnitude of the correction increasing with
invariant mass. We argue that a thermal description is reliable for invariant
masses less than $M_{max}\approx(2\tau_0 T_0^2)/(\eta/s)$. For reasonable
values of the shear viscosity and thermalization time $M_{max}\approx 4.5$ GeV.
Finally, the early emission from a viscous medium is compared to emission from
a longitudinally free streaming plasma. Qualitative differences in $q_\perp$
spectrum are seen which could be used to extract information on the
thermalization time, viscosity to entropy ratio and possibly the thermalization
mechanism in heavy-ion collisions.
