Under this section of UpToDate you are provided information on the interaction of multiple drugs with each other. You must first perform a drug keyword search. Below is a sample search for the interaction of the drug Metformin and alcohol.
After entering your initial search for a drug, you are presented with the following screen, which lists the number of different drug interactions that are available for the drug "Metformin".
To add one or more additional items to the list simply key in the name of the additional drug and click on analyze.