Drug interactions
Lorazepam + Thioridazine
Severity: Moderate
Lorazepam and Thioridazine: 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
Concurrent use increases sedation, dizziness and hypotension, and thioridazine's strong anticholinergic and alpha-blocking effects can add to the burden. Thioridazine carries QT prolongation risk by itself, and oversedation or falls may complicate care.
What this interaction means in plain words
Lorazepam and Thioridazine 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; Thioridazine belongs to Central Nervous System.
Why it happens
Additive CNS depression via GABA-A potentiation and thioridazine's antihistaminic, anticholinergic and alpha-adrenergic blockade.
What to do
Monitor sedation and orthostatic blood pressure, and use the lowest effective doses. Keep electrolytes and ECG monitoring in line with thioridazine requirements.
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 Thioridazine
- Abiraterone + Thioridazine Contraindicated
- Adagrasib + Thioridazine Contraindicated
- Amiodarone + Thioridazine Contraindicated
- Amisulpride + Thioridazine Contraindicated
- Amitriptyline + Thioridazine Contraindicated
- Amoxapine + Thioridazine Contraindicated
Frequently asked questions
Can I take Lorazepam with Thioridazine?
MediHelp rates the interaction as moderate. Lorazepam and Thioridazine 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. Concurrent use increases sedation, dizziness and hypotension, and thioridazine's strong anticholinergic and alpha-blocking effects can add to the burden. Thioridazine carries QT prolongation risk by itself, and oversedation or falls may complicate care.
How serious is the interaction between Lorazepam and Thioridazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor sedation and orthostatic blood pressure, and use the lowest effective doses. Keep electrolytes and ECG monitoring in line with thioridazine requirements.
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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