Why exactly are you not supposed to drink with a straw after a tooth extraction?

Negative pressure: To suck liquid with straw, you need to create negative pressure in your mouth. That will cause bleeding from root.

Clot dislodgment: The answer given by another doctor is not quite accurate, as it states it will cause bleeding from the root. I understand what the person is thinking i suppose, but extraction of a tooth means the crown and the root. The reason is: sucking pressure can easily dislodge a recent clot, thereby exposing alveolar bone to the oral environment, it is called a dry socket. Clot loss due to suction.