Drug interactions
Hydromorphone + Primidone
Severity: Major
Hydromorphone and Primidone: major 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 metabolized to phenobarbital, so it adds barbiturate CNS depression to opioid effects. This raises the risk of marked sedation and respiratory depression.
What this interaction means in plain words
Hydromorphone and Primidone can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Hydromorphone belongs to Musculoskeletal; Primidone belongs to Central Nervous System.
Why it happens
Additive CNS and respiratory depression from barbiturate activity and opioid agonism.
What to do
Monitor sedation and respiratory rate, and start the opioid at a reduced dose in patients on primidone.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Hydromorphone
- Alvimopan + Hydromorphone Contraindicated
- Bupropion-naltrexone + Hydromorphone Contraindicated
- Hydromorphone + Isocarboxazid Contraindicated
- Hydromorphone + Olanzapine / samidorphan Contraindicated
- Hydromorphone + Phenelzine Contraindicated
- Hydromorphone + Tranylcypromine Contraindicated
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 Hydromorphone with Primidone?
MediHelp rates the interaction as major. Hydromorphone and Primidone can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Primidone is metabolized to phenobarbital, so it adds barbiturate CNS depression to opioid effects. This raises the risk of marked sedation and respiratory depression.
How serious is the interaction between Hydromorphone and Primidone?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor sedation and respiratory rate, and start the opioid at a reduced dose in patients on primidone.
What other medicines interact with Hydromorphone?
MediHelp also lists interactions of Hydromorphone with, for example, Alvimopan, Bupropion-naltrexone, Isocarboxazid. The full list is on the Hydromorphone page.
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