Tricyclic Antidepressants Can Produce Delirium

Tricyclic antidepressants can produce delirium. Which of the following is true about this effect?

A) The delirium is considered beneficial in treating depression
B) Increasing the TCA dosage usually alleviates the problem
C) The delirium is due to increased 5-HT receptor stimulation
D) The antimuscarinic activity of this class is thought to be at the cause
E) Is usually a prelude to the onset of seizures