Authors:

But money spent while manic doesn't fit into the Internal Revenue Service concept of medical expense or business loss. So after mania, when most depressed, you're given excellent reason to be even more so.

Frederick K. Goodwin, Kay Redfield Jamison (2007). “Manic-Depressive Illness: Bipolar Disorders and Recurrent Depression”, p.40, Oxford University Press
But money spent while manic doesn't fit into the Internal Revenue Service concept of medical expense or business loss. So after mania, when most depressed, you're given excellent reason to be even more so.