My husband was also on Sinemet 25/100 for a short time. Again the dose was slowly increased but it had no effect and seemed to make it worse. We didn't believe it was PD either. He has just had a DaTScan that shows it is definitely PD and is now taking Azilect and Requip, again slowly increasing the doses and up to now no side-effects. His neurologist says this time medication will work and believes the reason it didn't before is he was so resistant to having PD. Reading this site though it seems everyone takes a while to sort out the meds.