Drug interactions
Carbidopa-entacapone-levodopa + Haloperidol
Severity: Major
Carbidopa-entacapone-levodopa and Haloperidol: major interaction.
Last updated Sources: UK SmPC
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Haloperidol is a potent D2 antagonist that can markedly worsen parkinsonism and counteract levodopa. Levodopa may also reduce the antipsychotic effect.
What this interaction means in plain words
Carbidopa-entacapone-levodopa and Haloperidol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Carbidopa-entacapone-levodopa belongs to Central Nervous System; Haloperidol belongs to Central Nervous System.
Why it happens
Pharmacodynamic antagonism through D2 receptor blockade.
What to do
Avoid haloperidol in patients taking levodopa. Use quetiapine or clozapine if an antipsychotic is needed, and monitor motor function.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Carbidopa-entacapone-levodopa and Haloperidol, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
- HALDOL 2 mg/ml oral solution - SmPC sections 4.3/4.5 (names the partner; "Haloperidol may antagonise the effect of levodopa and other dopamine agonists.") — electronic medicines compendium (UK SmPC)
Other interactions of Carbidopa-entacapone-levodopa
- Carbidopa-entacapone-levodopa + Isocarboxazid Contraindicated
- Carbidopa-entacapone-levodopa + Phenelzine Contraindicated
- Carbidopa-entacapone-levodopa + Selegiline transdermal Contraindicated
- Carbidopa-entacapone-levodopa + Tranylcypromine Contraindicated
- Amisulpride + Carbidopa-entacapone-levodopa Major
- Asenapine transdermal + Carbidopa-entacapone-levodopa Major
Other interactions of Haloperidol
- Dofetilide + Haloperidol Contraindicated
- Dronedarone + Haloperidol Contraindicated
- Haloperidol + Ibutilide Contraindicated
- Haloperidol + Levoketoconazole Contraindicated
- Haloperidol + Panobinostat Contraindicated
- Haloperidol + Pimozide Contraindicated
Frequently asked questions
Can I take Carbidopa-entacapone-levodopa with Haloperidol?
MediHelp rates the interaction as major. Carbidopa-entacapone-levodopa and Haloperidol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Haloperidol is a potent D2 antagonist that can markedly worsen parkinsonism and counteract levodopa. Levodopa may also reduce the antipsychotic effect.
How serious is the interaction between Carbidopa-entacapone-levodopa and Haloperidol?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid haloperidol in patients taking levodopa. Use quetiapine or clozapine if an antipsychotic is needed, and monitor motor function.
What other medicines interact with Carbidopa-entacapone-levodopa?
MediHelp also lists interactions of Carbidopa-entacapone-levodopa with, for example, Isocarboxazid, Phenelzine, Selegiline transdermal. The full list is on the Carbidopa-entacapone-levodopa page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
