Drug interactions
Loxapine + Perphenazine
Severity: Moderate
Loxapine and Perphenazine: moderate interaction.
Last updated
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
Two antipsychotics with dopamine-blocking activity together increase the risk of extrapyramidal symptoms, sedation, anticholinergic effects and neuroleptic malignant syndrome. They can also increase QT prolongation and orthostatic hypotension.
What this interaction means in plain words
Loxapine and Perphenazine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Loxapine belongs to Central Nervous System; Perphenazine belongs to Central Nervous System.
Why it happens
Additive dopamine D2 blockade and sedative, anticholinergic and hypotensive effects.
What to do
Avoid antipsychotic polypharmacy where possible. If both are needed, monitor for extrapyramidal symptoms, sedation, hyperthermia and rigidity, and use the lowest effective doses.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Perphenazine
- Ibutilide + Perphenazine Contraindicated
- Perphenazine + Pimozide Contraindicated
- Perphenazine + Thioridazine Contraindicated
- Adagrasib + Perphenazine Major
- Alfentanil + Perphenazine Major
- Amiodarone + Perphenazine Major
Other interactions of Loxapine
- Alfentanil + Loxapine Major
- Alprazolam + Loxapine Major
- Amisulpride + Loxapine Major
- Amoxapine + Loxapine Major
- Apomorphine + Loxapine Major
- Belladonna and opium + Loxapine Major
Frequently asked questions
Can I take Loxapine with Perphenazine?
MediHelp rates the interaction as moderate. Loxapine and Perphenazine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Two antipsychotics with dopamine-blocking activity together increase the risk of extrapyramidal symptoms, sedation, anticholinergic effects and neuroleptic malignant syndrome. They can also increase QT prolongation and orthostatic hypotension.
How serious is the interaction between Loxapine and Perphenazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid antipsychotic polypharmacy where possible. If both are needed, monitor for extrapyramidal symptoms, sedation, hyperthermia and rigidity, and use the lowest effective doses.
What other medicines interact with Perphenazine?
MediHelp also lists interactions of Perphenazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Perphenazine page.
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