I am not aware of flu shots ever having caused problems for SCLS patients who are on the recomended treatment with IVIG. I have had a flu shot every year since I initiated my successful IVIG treatment sequence 8 years ago this week, and it's never been a problem. However, SCLS patients who are not receiving IVIG are caught between a rock and a hardplace: on the one hand, they don't want to do anything that could trigger an episode of SCLS, like getting a flu shot. On the other, as illustrated by Ruth's comment, the onset of a flu might conceivably trigger an episode of SCLS. I purposely didn't get the flu shots before my SCLS was brought under control. The question posed is whether doctors tell SCLS patients that it is necessary for them to get flu shots. I don't know the answer, but I cannot imagine any physician telling their SCLS patient that they must expose themselves to an unknown risk by getting a flu shot -- especially if their patient has not been stabilized through the recommended and highly effective therapy with IVIG.