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Dr. G. - Increase in meds.
Carl_1970 posted:
H again Dr. G,

I have been requested to increase my Quetiapine from 400mg XR to adding 150 mg of non XR for anxiety over the next few days.

Please could you advise me of what side-effects I should expect and when the medication should take effect.

Many thanks,

Joseph F Goldberg, MD responded:
Dear Carl,

There is no known difference in the effects of quetiapine XR versus non-XR in known effects regarding mood or anxiety; it is the same drug. The non-XR is thought by some to cause a faster sedating effect than the XR form, otherwise there aren't really known differences in the effect of either the drug on the body. Chances are, the antihistamine effects of the XR are already maximized so I'm not sure a higher dose would necessarily yield much difference in this range unless the target symptoms were psychosis or mania. Doses of quetiapine at 300 mg/day are known to treat depression, though higher doses have not shown a greater antidepressant benefit. Doses in the 400-800 mg/day range are more commonly used to treat psychosis or mania.

Dr. G.
Carl_1970 replied to Joseph F Goldberg, MD's response:
Hi again Dr.G

I was prescribed 600mg when I was originally diagnosed as the treatment dose. I remained on this for 2 years before being allowed to reduce it to 500mg over 4 months, then 400mg for 8 months, then 300mg in March this year.

Due to stress at work, I have had a relapse.

Please would you advise me as to whether I would be less susceptible to a relapse if I was on a higher dose than the 300 mg?

Many thanks,

Joseph F Goldberg, MD replied to Carl_1970's response:
Dear Carl, Everyone is different and one size does not fit all, and your doctor is the only one who can make specific treatment recommendations for you. That said, in the studies of relapse prevention with Depakote or lithium plus seroquel or placebo, the average seroquel dose was about 550 mg/day. Dr G
Carl_1970 replied to Joseph F Goldberg, MD's response:
Dr. G,

Thank you very much for your reply and the information.

I am only taking Seroquel at the moment, 50 mg in the morning and 550 mg at night as a treatment dose.

Please would you inform me as to how long it should take for this increased dosage (from 300mg) to have full effects?


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