a person was poisoned at a restaurant riddle

A man and a woman went to a restaurant for dinner.

While they were waiting for the main dish, she ordered 5 drinks with ice because it was very hot.

The woman drank 4 of them all at once, while the man only drank one.

After a while, the man became ill and died.

The doctors said that all the drinks were poisoned.

The ice were poisoned ,may be the man drank it after ice was melted.