Available for licensing are new methods of rapidly treating depression. The drugs currently used to treat depression work by increasing the activity at serotonin, norepinephrine and perhaps dopamine receptors in the CNS. However these drugs are effective in only 60-70% of patients, require 3-4 weeks of treatment before clinical improvement and have many side effects. These inventors have shown that in human patients, the administration of anti-muscarinic agents produces a rapid, prolonged alleviation of depressive symptoms. Beginning the day following administration of the anti-muscarinic agent, a majority of patients show significant improvements in mood, anxiety, sleep and other depressive symptoms that last days or weeks. The very slow dissociation of some muscarinic agents from their receptors may account for the prolonged therapeutic effects.