I am on 10 mg celexa and I have started feeling better. I have been on that for almost 3 wks. I was hoping that was all I would have to take or no more than 20 mg. I want to find the lowest therapeutic dose not rush up so fast. but could a person then lower it with out any problem. I didn't know these drugs were so tricking. It is making me feel so weird about them.
Antidepressants are not like aspirin where taking 2 tablets gives a doubling of the effect of 1 tablet. They work by boosting the production of new brain cells
to replace those damaged by stress hormones. There is a minimum dose required to initiate and sustain this reaction which varies from person to person, but for Celexa is usually at least 20mg. Many need more. It can be counterproductive to take less than is needed. Doing so doesn't actually achieve anything, the side-effects tend to be the same if you take a sub therapeutic dose as when taking an effective one.
Nor does taking more than is needed do any harm provided the dose is within the safe range. For example, antidepressants have no affect on those without an anxiety or depressive disorder apart from the side-effects. A study in rats is a good illustration of this (Zangen A, 1997 - Abstract
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). Rats genetically predisposed to depression have up to 8 times more serotonin in areas of the brain associated with depression than in unaffected controls. Treatment with antidepressants reduces their serotonin levels to normal amounts, but has no effect on the levels of the controls.
For more on this and the other brain changes seen in the various anxiety disorders see: CNS Image Bank:
Anxiety - Anxiety Disorders