It appears to be legitimate pain for many. The receptors for the brain, even in aliens that should be able to control that sort of thing [like he and T'Pol] still register the pain, even if there are no wounds. So the treatment in that case stands.

But the existence of the pain I'm worrying can create more physical effects. And at the moment I'm also concerned that, do to the irregularity, genuine physical symptoms may start showing up soon.

[It's a little disappointing to hope that the death toll just stays as it is and doesn't progress.]