I had a Ketamine Infusion in October 2015 and while I was in the hospital I transitioned from Fentanyl to Palexia. Palexia seemed to do the trick for a while but eventually it stopped covering the pain - could have been that the Ketamine effects wore off ... anyway - doc tried increasing my dosage but I didn't tolerate it well. In January this year, after trying to cope for 14 months my doc and I decided it was time for a change. Am now back on OxyContin plus Endone PRN and Diazepam as needed for spasms.
Worst part of Palexia for me was the weight gain. Over the space of 14 months I put on 14kg without changing my eating or mobility habits. Thankfully, with the change to OxyContin, the weight has stopped increasing. In fact I've actually dropped a couple of kg.None of the paraphernalia refers to weight gain as a side effect so it took a while to convince the doc I was right. She believes me now!
If you are on this medication and you are gaining weight for no reason - make a big noise about it and beg for a medication change. Carrying around all that extra weight just makes it harder to cope and looking in the mirror everyday at the round ball you have become is way too depressing.