There is none. Colds and flu are caused by viruses. They are nasty little critters that for the most part, defy a cure other than time as the inmune system defeats them.
The best you can do is stay warm, drink lots of fluids and get plenty of rest. You could try treating the symptoms which can vary from one person to another and from one virus to the next but help will be marginal. If you had pneumonia, caused by bacteria, it could be cured with an antibiotic, with penecillian being the most common one used. Treating the symptoms offers only "some" help.
You can probably expect your symptoms of a runny nose, caughing and a general rotten feeling wilto remain until your imune system defeaats the virus. Just repeat, "Go, killer T cells; Go!" over and over again.
Rollin