Prime Minister John Key says he is fit, healthy and able to work, despite fainting at a resturant in Christchurch on Thursday night.
He was taken to hospital where he was seen by three specialists, who gave him the all-clear.
Mr Key is now in Antarctica for three days.
On landing at Scott base on late on Friday, Mr Key told reporters he is feeling much better.
He said he would never have made the trip if he was not confident about his health.