Severe constipation, please help

I have to make this a bit short since I'm at work.

The medicine I am on has given me constipation I can usually deal with alright. A few times, my stool was extremely oversize and hard, and I almost had to go to the emergency room to pass it. It is the most painful experience of my life when that happens. Well today I just went to go the bathroom, and it is going to happen again. I can feel a very large solid stool and I am basically afraid to deal with this.

Stool softeners just screw up my digestive system. Is there something I can inject anally which will break down the stool fast, like within an hour? Lubrication doesn't help a whole lot, it needs to be broke down. Please help. Thanks