My mother, age 78, is taking Viibryd and has a very long history taking almost innumerable antidepressants and bipolar meds. She is having unusual side effects that are most likely a result of the new med, including paranoid thoughts and ideation, black or white thinking, a nervous vocal tic that has her making these cooing, humming sounds involuntarily, and other strange side effects. Is tolerance to this hybrid drug really a matter of dosage level, or is it more like you can either tolerate it and enjoy relief from depression, or you will enjoy no positive effects, only ill effects?