Drug interactions
Diazepam + Lorazepam
Severity: Moderate
Diazepam and Lorazepam: 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
Taking two benzodiazepines together adds to sedation, psychomotor impairment and respiratory depression without a meaningful gain in anxiolytic or anticonvulsant effect. Risk is greatest in older adults, in patients with respiratory disease and when opioids or alcohol are also used.
What this interaction means in plain words
Diazepam and Lorazepam 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.
Diazepam belongs to Musculoskeletal; Lorazepam belongs to Central Nervous System.
Why it happens
Additive enhancement of GABA-A receptor mediated CNS depression.
What to do
Avoid routine concurrent use of two benzodiazepines and use a single agent at the lowest effective dose. If overlap is unavoidable, such as during a switch, monitor sedation and respiratory status.
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 Diazepam
Other interactions of Lorazepam
Frequently asked questions
Can I take Diazepam with Lorazepam?
MediHelp rates the interaction as moderate. Diazepam and Lorazepam 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. Taking two benzodiazepines together adds to sedation, psychomotor impairment and respiratory depression without a meaningful gain in anxiolytic or anticonvulsant effect. Risk is greatest in older adults, in patients with respiratory disease and when opioids or alcohol are also used.
How serious is the interaction between Diazepam and Lorazepam?
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 routine concurrent use of two benzodiazepines and use a single agent at the lowest effective dose. If overlap is unavoidable, such as during a switch, monitor sedation and respiratory status.
What other medicines interact with Diazepam?
MediHelp also lists interactions of Diazepam with, for example, Calcium / magnesium / potassium / sodium oxybates, Alfentanil, Alprazolam. The full list is on the Diazepam page.
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