Is it possible that adding Bupropion to Brintellix makes my hands shake and I can't sleep?

Yes, most likely, these symptoms are caused by medications. You increased your dose of Brintellix and then added bupropion, which causes an additional increase in Brintellix blood levels. Such a therapeutic combination may expose you to a greater extent to the so-called serotonin syndrome. It is manifested by: irritability, confusion, arrhythmias, pressure fluctuations, muscle tremors or their stiffness, gastrointestinal problems. It is not said that your symptoms are serotonin syndromes, because it is very rare. It is also not my aim to make you afraid of this effect, but only to inform you about the possibility of its occurrence. It is very likely, however, that they are associated with a rapid increase in serotonin levels in the body caused by a change in the dosage of drugs. In my opinion, such treatment requires a new consultation with a doctor who will confirm the advisability of using two components that enter into a rare but health-threatening interaction. However, please do not stop taking your medication yourself, because this can also cause negative health consequences for you. On GdziePoLek you can also use online teleadvice: https://www.gdziepolek.pl/telekonsultacja I also attach articles that may be useful: https://www.gdziepolek.pl/artykuly/depresja https://www.gdziepolek.pl/artykuly/czy-mozna-laczyc-leki-ze-soba