Diphenhydramine May Be Useful as a Palliative Treatment for Patients Dying With Parkinson’s Disease and Tremors: A Case Report and Discussion

Diphenhydramine is an antihistamine with anticholinergic properties, which has been used for the treatment of Parkinson disease (PD) prior to the development of newer agents with better side-effect profiles. However, most of these agents are given orally. Unfortunately, at the time of death, patients with paralysis agitans are no longer able to swallow and they can experience worsening of their tremors. We report the case of 1 patient with congestive heart failure (CHF) and PD who was unable to swallow and developed uncontrollable tremors 24 hours prior to death and whose tremors were successfully treated with diphenhydramine. We feel that in preimminent patients who cannot swallow or may not have perioral endoscopic gastrostomy (PEG)s or feeding tubes, parenteral diphenhydramine may be an appropriate palliative intervention to reduce tremors.