Pain from Cialis?

Gents:

Having had daVinci surgery for Gleason 6 prostate cancer in 2011, I have been using Cialis for well over 3 years now.  I was taking a 5 mg. dose immediately after surgery and then switched to varying does over the years to help with my ED.  At 2 years post surgery, I fortuantely recovered to the degree where I really didn't need any Cialis, but contiued taking it for that extra "boost".  During this time I developed severe aching in my knees and tendons of my legs.  It was so bad that it interferred with my sleep.  about 2 weeks ago, I stopped taking all Cialis and I no longer have this nagging pain. Do you think that the Cialis was indeed the cause? Has anyone else experienced this?  According to Cialis website, such pain as a side effect is very very rare.

Thanks,

Bill K. from NJ

June 2011 PSA 3.3, Free PSA 21%, Biopsy 1 of 12 +, Gleason 3+4

DaVinci July 2011, Downgraded to 3+3 = 6, 10% involvement, contained, 67 grams

Immediate urinary control, but severe ED for 13 months, now almost 100% of former function.

all PSA's since <0.015.

I think it's a common side effect. My doc switched me to Levitra because it has less of that SE. I had horrific pain while on Cialis prior to surgery, but my wife had slipped me grapefruit one day. Later I read the fine print and found they say not to eat grapefruit. After surgery and before starting bi-mix I used Levitra and also tried a half dose (2.5mg) Cialis. At that dose and without grapefruit I was ok for pain. Even though insurance doesn't cover bi-mix (yet) it's much less expensive than the coverage I would get on Levitra. Actually they only cover Cialis or Viagra now, so Levitra would be full retail price.