Heterocyclic amides of formula (1) wherein: is a single or double bond; A is phenylene or heteroarylene; m is 0, 1 or 2; n is 0, 1 or 2; R1 is selected from for example halo, nitro, cyano, hydroxy, carboxy; R2 is hydrogen, hydroxy or carboxy; R3 is selected from for example hydrogen, hydroxy, aryl, heterocyclyl and C1-4alkyl(optionally substituted by 1 or 2 R8 groups); R4 is independently selected from for example hydrogen, halo, nitro, cyano, hydroxy, C1-4alkyl, and C1-4alkanoyl; R8 is selected from for example hydroxy, —COCOOR9, —C(O)N(R9)(R10), —NHC(O)R9, (R9)(R10)N— and —COOR9; R9 and R10 are selected from for example hydrogen, hydroxy, C1-4alkyl (optionally substituted by 1 or 2 R13); R13 is selected from hydroxy, halo, trihalomethyl and C1-4alkoxy; or a pharmaceutically acceptable salt or pro-drug thereof; possess glycogen phosphorylase inhibitory activity and accordingly have value in the treatment of disease states associated with increased glycogen phosphorylase activity. Processes for the manufacture of said heterocyclic amide derivatives and pharmaceutical compositions containing them are described.