Drug interactions
Lorazepam + Primidone
Severity: Moderate
Lorazepam and Primidone: 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
Primidone is metabolised to phenobarbital, and combining it with lorazepam produces additive sedation and respiratory depression. Dizziness, ataxia and cognitive impairment may be increased.
What this interaction means in plain words
Lorazepam and Primidone 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; Primidone belongs to Central Nervous System.
Why it happens
Additive GABA-A mediated CNS depression from phenobarbital, the active metabolite of primidone, and the benzodiazepine.
What to do
Monitor sedation and respiratory function, and adjust doses when starting or changing either drug. Counsel patients about driving and fall risk.
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 Primidone
- Lorlatinib + Primidone Contraindicated
- Lurasidone + Primidone Contraindicated
- Primidone + Ranolazine Contraindicated
- Primidone + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
- Primidone + Voriconazole Contraindicated
- Abiraterone + Primidone Major
Frequently asked questions
Can I take Lorazepam with Primidone?
MediHelp rates the interaction as moderate. Lorazepam and Primidone 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. Primidone is metabolised to phenobarbital, and combining it with lorazepam produces additive sedation and respiratory depression. Dizziness, ataxia and cognitive impairment may be increased.
How serious is the interaction between Lorazepam and Primidone?
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 respiratory function, and adjust doses when starting or changing either drug. Counsel patients about driving and fall risk.
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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