Difference between In drink and In the drink

in drink—(coll.) said of smth. done or spoken when drunk:

• It was spoken in drink, but it happened to be true.

Note: The expression is not equivalent in meaning to the phrase on the drink—(coll.) indulging in alcohol:

• Her brute of a husband was always on the drink and gamble.

in the drink—(coll.) in the sea or river:

• “This means absolutely everything to me,” said Hopp, all wet after his son threw him in the drink.