I found something that has helped me relieve my pain/spasms and wanted to share. I do not get a spasm or pain until 2-3 hours after a BM. So I prepare for the ouch by applying the nitroglycerin and then sit on a heating pad (on medium). It tends to cause me a worse headache using the heat w/ the cream, but the pain in the ass is greatly reduced. Maybe 20 minutes and it is bearable again. Another plus, this is how I can manage the pain while at work (everyone thinks I have a really bad back!).
I hope this helps someone, somewhere!