In the RotaTeq clinical trials in the first week after any dose vaccine recipients had a small but statistically significant increased rate of diarrhea (18.1% in the RotaTeq group, 15.3% in the placebo group) and vomiting (11.6% in the RotaTeq group, 9.9% in the placebo group). During the 42-day period following any dose, statistically significantly greater rates of diarrhea, vomiting, otitis media, nasopharyngitis and bronchospasm occurred in RotaTeq recipients compared with placebo recipients.
In the Rotarix clinical trials, in the first week after vaccination, Grade 3 (i.e., those that prevented normal everyday activities) cough or runny nose occurred at a slightly but statistically higher rate in the Rotarix group (3.6 %) compared with placebo group (3.2%). During the 31-day period after vaccination, these unsolicited adverse events occurred at a statistically higher incidence among vaccine recipients: irritability (11.4% in Rotarix group, 8.7% in placebo group) and flatulence (2.2% in Rotarix group, 1.3% in placebo group).
In clinical trials of both vaccines the occurrence of intussusception was studied very carefully; see the separate question and answer on this topic.