I have been taking Cetalopram 40mg for about 4 years , because of depression caused by marriage breakup, problems with my teenage daughter on drugs , looking after my elderly mother etc. I have been coping reasonably well up to the last 6 months, now i feel tired all the time , anxious, unable to cope. Would i be able to try a different anti depressant do you think, im just wondering if my body has become immune to Cetalopram. Bev