or who's had a bad reaction to namenda xr or its ingredients. before starting treatment, tell their doctor if they have, or ever had, a seizure disorder, difficulty passing urine, liver, kidney or bladder problems, and about medications they're taking. certain medications, changes in diet, or medical conditions may affect the amount of namenda xr in the body and may increase side effects. the most common side effects are headache, diarrhea, and dizziness. he's always been my everything. now i am giving back. ask their doctor about adding once-daily namenda xr. and i quit smoking with chantix. my children always wanted me to quit smoking but i resigned myself to the fact that it wasn't going to work. but chantix helped me do it. along with support, chantix (varenicline) is proven to help people quit smoking. it gave me the power to overcome the urge to smoke. some people had changes in behavior, thinking or mood, hostility, agitation, depressed mood and suicidal thoughts or actions while taking or after stopping chantix. some people had seizures while taking chantix. if you have any of these, stop chantix and call your doctor right away.