Green’s Dictionary of Slang

(drugs) a combination of glutethimide and codeine cough syrup.

1993		E. Richards Cocaine True 23: Taiwal, you snort it. It’s mixed with codeine and doctors sell it [...] If you get a pill, they call it pancake and syrup. A lot of little kids are doing pancakes and syrup.
1997		L. Pettiway Workin’ It 183: I was taking reds, red devils, [...] pancakes and syrup.
2001		ONDCP Street Terms 16: Pancakes and syrup — Combination of glutethimide and codeine cough syrup.