time of effectiveness of zofran
How to use Zofran. To prevent nausea from chemotherapy, take this medication by mouth usually within 30 minutes before treatment begins. To prevent nausea from radiation treatment, take this medication by mouth 1 to 2 hours before the start of your treatment. To prevent nausea after surgery, take ondansetron by mouth 1 hour before the start of surgery. This medication may be taken with or without food. However, your doctor may tell you not to eat before chemotherapy, radiation, or surgery.
There are three, recent large studies that provide the best information we have on the safety of Zofran use during pregnancy. The first study was important in showing no complications in pregnancy from Zofran, but the question of birth defects was not quite answered because half of the patients started Zofran after 10 weeks gestation, which is after the critical time for organ development in the embryo.