Okay, if the problem continues to persist, return to the Emergency Room if you do not have a regular physician/psychiatrist. The therapist he is seeing is taking a conservative approach, but if the medication is exacerbating the issues, then it must be changed. The atypical anti-psychotics work rather quickly, as your son discovered.
Here are a couple of thoughts: (1) I don't know enough about your son, your history, or the symptoms that landed him in the ER (impossible to diagnose over the internet, of course), but I am wondering if he may have had a panic attack rather than a manic episode. Mania in kids doesn't tend to pop up out of nowhere at 17 without some behavioral manifestations earlier in life - plus, the acute nature (to send him to the ER) could be panic disorder - which is tripped by anxiety which is also tripped by serotonin dysregulation, which may have been irritated by the Saphris. Whew... that was a long sentence - sorry. and (2) It may be that he needs a mood stabilizer rather than the anti-psychotic. Either way, there are a lot of medications to choose from for bi-polarity. The science is not as exact with kids as with adults (the brain is still developing, thereby creating a moving target), so the physicians do the best they can in the short run.
My overall sage wisdom is to get a psychiatrist as quickly as you can, but I know you are doing that already. He needs somebody to follow him closely for awhile to gage the strength and selection for the meds to hit his exact metabolism and chemistry. In the meantime, use the ER if you have no better option.
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