Last December, the FDA approved a new high-dose flu shot that is four times as strong as previous seasonal flu shots. This new shot is designed to increase the antibody response for older adults, who are more susceptible to the respiratory flu. Research has shown higher antibody titres, but there is no evidence that this shot will translate into fewer patients getting the flu. Complication rates and mercury levels used as preservatives in the shots are not clear at this time. Caution is suggested for now.
See Family Practice News (click here), June 1, 2010, p. 15 and the FDA report on Fluzone High Dose (click here).