Drug interactions
Lorazepam + Perphenazine
Severity: Moderate
Lorazepam 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
Both agents depress the CNS, so the combination can increase sedation, impair psychomotor performance and cause hypotension. It is commonly used deliberately in agitation, but the additive effects need attention.
What this interaction means in plain words
Lorazepam 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.
Lorazepam belongs to Central Nervous System; Perphenazine belongs to Central Nervous System.
Why it happens
Additive CNS depression through GABA-A enhancement and dopaminergic, histaminic and adrenergic blockade.
What to do
Use the lowest effective doses and monitor sedation, blood pressure and respiration. Take extra care in older patients and those with respiratory disease.
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 Lorazepam
Other interactions of Perphenazine
- Ibutilide + Perphenazine Contraindicated
- Perphenazine + Pimozide Contraindicated
- Perphenazine + Thioridazine Contraindicated
- Adagrasib + Perphenazine Major
- Alfentanil + Perphenazine Major
- Amiodarone + Perphenazine Major
Frequently asked questions
Can I take Lorazepam with Perphenazine?
MediHelp rates the interaction as moderate. Lorazepam 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. Both agents depress the CNS, so the combination can increase sedation, impair psychomotor performance and cause hypotension. It is commonly used deliberately in agitation, but the additive effects need attention.
How serious is the interaction between Lorazepam 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: Use the lowest effective doses and monitor sedation, blood pressure and respiration. Take extra care in older patients and those with respiratory disease.
What other medicines interact with Lorazepam?
MediHelp also lists interactions of Lorazepam with, for example, Alfentanil, Alprazolam, Amobarbital. The full list is on the Lorazepam page.
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