Side Effects from H1N1 Vaccines

By Julie Stachowiak, PhD
Multiple Sclerosis Guide; Guest blogger

I recently posted the links to the package inserts for all four H1N1 vaccines. The thing that I imagine many people will want to check out for themselves is the list of side effects for these vaccines. These package inserts are a good place to look, as they list all of the side effects that were noted during the clinical trials, as well as the frequency that they occur. (Read carefully - the side effects mentioned were for the clinical trials on the seasonal (trivalent) flu vaccines, not the H1N1 vaccines, but are assumed to be the same for both vaccines.)

When looking at the side effects charts, do not forget to compare the rates of the vaccine side effects to that of the control group - and figure out what the control group is given - to really tell you what is going on. For instance, the FluMist charts tell you that in one study, 58% of the kids developed "runny nose/nasal congestion," which seemed unacceptable to me until I read that 50% of kids getting placebo (completely inert substance) also had the same side effects.

I had to laugh when I read the rates of "decreased appetite" and "irritability" - which were also really close in vaccine vs. placebo. It was funny to me, because "snotty," "picky" and "cranky" describes quite a few children (including my own) on any given day.