My sister took 1600milligrams of Seroquol and was only suppose to take 400. What do ?

She must seek medical attention IMMEDIATELY. If treated in time, before the drug is absorbed into the body, the stomach need only be pumped out, otherwise other measures must be taken, intravenous for dehydration being one of them. There are many side effects of taking an overdose of this medication, one being very low blood pressure.