What will happen if you take 10 citalopram (20mg) at once?

Never safe: it is never safe to take more medications then prescribed by your physician. go to the ER for appropriate care and treatment.

Why?: I am not sure why you would ask such a question. The maximum daily dose of vital open is 40 mg. higher doses have been associated with serious heart arrhythmias. If you have accidentally taken that many or are considering suicide you should call 911 or go to the nearest hospital