Hi germaine, welcome... Here's a list of side effects for Forteo from Pubmedhealth http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000227/
It doesn't specifically mention knee pain, but leg cramps are listed. I would discuss this with your Doctor and see what the solution maybe.
I took this medication for 2 years, and didn't have any side effects. However, since we all react differently to meds, it's difficult to say who will have side effects and who won't.
Good luck finding out about this...
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