In Reply

Correspondence Clinical Practice Guideline: The Palliative Care of Patients With Incurable Cancers by PD Dr. med. Steffen T. Simon, Dr. med. Anne Pralong, Prof. Dr. med. Lukas Radbruch, Prof. Dr. med. Claudia Bausewein, and Prof. Dr. med. Raymond Voltz in issue 7/2020

Gahr and Connemann rightly note that the evidence for haloperidol is limited. Overall, the treatment of nausea and vomiting in the palliative setting is supported by little evidence. Furthermore, the choice of drug classes and of pharmacological mechanisms of action is also limited. These issues are discussed in more detail in the long version of the guideline. We also refer to the long version of the guideline regarding the question of off-label use.

We agree that the discussion about the risk of cardiac repolarization disorders and of extrapyramidal side effects, due in particular to haloperidol, is essential. Important adverse drugs reactions are described in the guideline. However, when balancing risks and benefits, it should be borne in mind that the doses mentioned in the guideline for haloperidol and levomepromazine are low compared to those recommended in psychiatric treatment (2). For haloperidol, the guideline states a single oral dose of 0.5–1 mg, and a usual maximum subcutaneous dose of 5 mg/24 h. In the psychiatric setting, the recommended dosages depend on the indication and are, for example, 2–10 mg/d (up to 20 mg/d) for the treatment of schizophrenia and schizoaffective disorders and 5–20 mg/d intramuscularly for states of acute agitation (2). The study cited by Gahr and Connemann that showed increased mortality as a result of antipsychotic treatment, especially haloperidol, relates to long-term use. Patients with a life-limiting disease were excluded from the analysis (3). Due to the limited treatment duration and the low doses used in treating nausea and vomiting, the risk for extrapyramidal side effects is clearly lower than when administered as an antipsychotic drug. Furthermore, intravenous administration of low doses of haloperidol does not seem to affect the QT interval (4).

DOI: 10.3238/arztebl.2020.0462b

On behalf of the authors

Dr. med. Anne Pralong

Zentrum für Palliativmedizin, Uniklinik Köln

Conflict of interest statement

The authors of all contributions declare that no conflict of interest exists.

References

1. Simon ST, Pralong A, Radbruch L, Bausewein C, Voltz R: Clinical practice guideline: The palliative care of patients with incurable cancers. Dtsch Arztebl Int 2020; 117: 108–15

2. Müller MJ, Benkert O: Antipsychotika. In Benkert O, Hippius H, (eds.): Kompendium der Psychiatrischen Pharmakotherapie. Berlin, Heidelberg: Springer Berlin Heidelberg 2019: 284–504

3. Lao K, Wong A, Wong I, et al.: Mortality risk associated with haloperidol use compared with other antipsychotics: An 11-year population-based propensity-score-matched cohort study. CNS Drugs 2020; 34: 197–206

4. Duprey MS, Al-Qadheeb N, Roberts R, Skrobik Y, Schumaker G, Devlin JW: The use of low-dose IV haloperidol is not associated with QTc prolongation: post hoc analysis of a randomized, placebo-controlled trial. Intensive Care Med 2016; 42: 1818–9