In the literature regarding delirium and agitation in palliative care, there are references of their worsening as the hours of the day flows from afternoon on, with an inversion of the awake-sleep cycle. We studied the frequency of the use of our protocol for the control of agitation. From June 18, 2007, to January 4, 2010, 27 (5.3%) patients from the 509 admitted were sedated intermittently 86 times, in strict compliance with the protocol, because of episodes of agitation. We verified that from 8 pm until 6 am, the number of observed cases clearly exceeds the expected cases, if the distribution was uniform. The reverse situation occurs in all other hours of the day. The chi-square goodness of fit test proves that the differences are statistically significant (P < .001).