That shrink should have his license pulled.
(That said, Buproprion is a miracle drug. As far as antidepressants go, it's in class all by itself.)
I'd like to emphasize that this is literally a true statement. It's what's called an atypical antidepressant [0] because it doesn't act in a way similar to other antidepressants.
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Annoying? You must be easily annoyed.
But, misused? Not if you agree with definition 3 on dictionary.com: "actually; without exaggeration or inaccuracy." [0]
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I remember asking my psychiatrist about the dosage because it seemed high to me. He told me that up to 450 mg was the recommended maximum, and that he did have a few patients who had been on stronger doses. I believe he said he knew of one patient on 750 mg, though he may have said 600 mg.
Just based on my personal experience, psychiatric drugs are highly variable. I did very well under Welbutrin, while even the smallest dosages of Effexor had me waking up with constant nightmares and a non-euphoric, altogether unpleasant "buzzed" feeling not unlike a hangover without the headache. I also know people who swear by Effexor.
Edit: Today I almost entirely mitigate my depression with natural light therapy.