What the label lists and what reports show
Haloperidol side effects
Haloperidol's FDA label lists its adverse reactions in its own words. FAERS holds 26,054 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is neuroleptic malignant syndrome (1,742 reports).
- Generic listed
- A presentation discontinued
- Boxed warning
Check it at the source: the haloperidol FDA label on DailyMed (effective April 23, 2026, PD-Rx Pharmaceuticals, Inc.); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsCardiovascular Effects Tachycardia, hypotension, and hypertension have been reported. QT prolongation and/or ventricular arrhythmias have also been reported, in addition to ECG pattern changes compatible with the polymorphous configuration of Torsades de pointes, and may occur more frequently with high doses and in predisposed patients (see WARNINGS and PRECAUTIONS ). Cases of sudden and unexpected death have been reported in association with the administration of haloperidol. The nature of the evidence makes it impossible to determine definitively what role, if any, haloperidol played in the outcome of the reported cases. The possibility that haloperidol caused death cannot, of course, be excluded, but it is to be kept in mind that sudden and unexpected death may occur in psychotic patients when they go untreated or when they are treated with other antipsychotic drugs. …
Table 1 . Adverse Reactions Reported by ≥1% of Haloperidol Decanoate-treated Patients in a Double- Blind Active Comparator-Controlled Clinical Trial with Fluphenazine Decanoate a Precise incidence for extrapyramidal…
This table is printed in the HALOPERIDOL DECANOATE label published by Somerset Therapeutics, LLC of December 18, 2023; the label quoted above does not print one.
| System/Organ Class Adverse Reaction | Haloperidol decanoate (n=36) % | Fluphenazine decanoate (n=36) % |
|---|---|---|
| Abdominal pain | 2.8 | 0 |
| Parkinsonism | 30.6 | 44.4 |
| Oculogyric crisis | 5.6 | 0 |
| Akinesia | 2.8 | 22.2 |
| Akathisia | 2.8 | 13.9 |
| Tremor | 2.8 | 0 |
| Headache | 2.8 | 0 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
Source: FDA drug label, PD-Rx Pharmaceuticals, Inc., effective April 23, 2026 (SPL set 533b0b4c-cbd6-4ec0-a333-8b04b5b43a1d), via openFDA; the full label on DailyMed
What do FAERS reports show?
26,054 reports list haloperidol among the medicines taken, each a report of something that happened, not proof the medicine caused it; 4,220 are coded as a death and 12,918 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 19 reactions below, 9 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Haloperidol: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions