When consuming alcoholic beverages in Punta Cana, consider skipping anything frozen or ice-cooled, as tap water is not safe to consume. Punta Cana's nightlife is limited to bars and only a handful of clubs, but one of the highlights is Imagine. If you're going out to local bars, you shouldn't drink anything with ice cubes or frozen drinks, just to be safe. As many of the previous posters have said, they certainly make frozen drinks.
We found that the drinks made in the lobby bar are the best. In the Dominican Republic and Punta Cana in general, it is safe to consume the ice served in drinks, as long as this ice comes from well-established and reputable hotels and resorts. These establishments have the appropriate equipment and systems for the proper treatment and filtration of water. I've heard that you have to be careful with frozen drinks in Punta Cana because of the bacteria on the ice.
It is not recommended to consume ice, water or other water-based beverages in commercial establishments outside the hotels and resorts of the Dominican Republic and Punta Cana. Every time I go to a resort in Punta Cana I try to drink cold drinks without ice, my favorite drink is the “baileys”, it is a sweet and creamy drink that does not require any preparation, I always make the observation to the waiter not to put ice on it and they agree to serve me with great pleasure.