Correspondence (letter to the editor): Adverse Effects of Antipsychotics Are Relevant in Palliative Care Too

The presented update of the S3 guideline on palliative care of patients with incurable cancers recommends for first line treatment of nausea and vomiting (not induced by tumor therapy) antidopaminergic substances, among others (1). Haloperidol is named as an example. Antipsychotic drugs “with a broad spectrum of action” are recommended as second line therapy, a term that is not used in psychopharmacotherapy and which does not allow any conclusions about substances other than levomepromazine, which is the example used in the article. Independently of this terminological question, the article does not give enough space to the discussion of several crucial aspects.

Firstly, the evidence in support of the effectiveness of haloperidol in treating nausea and vomiting in palliative care is not consistently regarded as sufficient, as can be concluded from a Cochrane review (2). Furthermore, the use of haloperidol (and all other antipsychotic drugs) in this indication is off-label use, with all consequences for information-education, documentation, and liability. Primarily, however the use of haloperidol (or other antipsychotic drugs) is associated with numerous adverse effects, some of which are clearly relevant in the palliative care setting. In addition to an increased risk for cardiac repolarization disorders, disturbances in the extrapyramidal motor system (EPMS), acute dystonias, choreiform and parkinsonian syndromes, as well as akathisia/tasikinesia can develop (3), which can severely impair a patient’s remaining quality of life. Disorders of the EPMS are possible for all antipsychotic drugs, but are particularly common for first generation antipsychotics (such as haloperidol and levomepromazine) as well as for other antipsychotic drugs with a high affinity to the dopamine D2 receptor (3). In addition to disorders of the EPMS, sedation, impaired mental functions—such as cognition, affect, and impetus (3)—and raised mortality as a result of treatment with antipsychotic drugs (especially haloperidol) need to be borne in mind (4).