20 of celexa is a high dose for an anxiety sufferer to start with
the effective dose range is 10 to 60, I would start at 5 then work up to 10 and later to 20, I would say your doc isnt familiar with prescribing antidepressants to anxiety sufferers, some valium type meds always help to get used to a new antidepressant, but shouldnt be taken if the AD sedates you
get a pillcutter from a pharmacy, they come in several types, cut the tablet into quarters
all tablets can be cut, except some time release ones then lose the time release feature
recovered former longtime anxiety and panic attack sufferer and helper of other sufferers but no training or qualifications in medicine or psychology, any remarks that may be taken as advice must be confirmed with doctor or other health professional 
