This depends on the method of IPC, there are a lot of them. If sockets are used, you can may be intersept / track the comunication with appropriate tool like WireShark or something else.
But consider the communication over shared memory / file. A one process writes to some file, the another one reads and vice versa: how do you want to intersept such a IPC?
Take a look at this Wiki site to see the main methods provided by UNIX / POSIX systems.