Butorphanol Injection and Perampanel: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Perampanel
Butorphanol Injection
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased risk of respiratory and CNS depression
Interaction Deep Dive
The rate of emergency department visits involving non-medical use of concomitant benzodiazepines and opioid analgesics increased significantly over the period from 2004 to 2011, and deaths from drug overdose involving concomitant benzodiazepines and opioid analgesics also increased. In a study, overdose deaths in patients who were dispensed both opioids and benzodiazepines were 10-fold greater than those dispensed opioids alone. Another study in the Veterans Health Administration demonstrated that patients taking opioids with a history of or current benzodiazepine prescription had an increased risk of death due to overdose compared with patients taking opioids without a history of benzodiazepine use; as daily benzodiazepine doses increased, risk of death due to drug overdose increased as well3. Reserve the concomitant use of butorphanol and CNS depressants to patients for whom alternatives are inadequate. If concomitant use is necessary, use the lowest dose and shortest duration necessary to achieve treatment goals. Consider using a lower dose of butorphanol or the CNS depressant and closely monitor for sedation and respiratory depression 21.
Why it happens (mechanism)
Additive CNS depression
Literature reports
2 reports — tap to read
a) The rate of emergency department visits involving non-medical use of concomitant benzodiazepines and opioid analgesics increased significantly over the period from 2004 to 2011, from 11 visits per 100,000 population to 34.2 visits per 100,000 population. Also, deaths from drug overdose involving concomitant benzodiazepines and opioid analgesics (including both prescribed doses and doses greater than prescribed) increased from 0.6 per 100,000 population to 1.7 per 100,000 population. The proportion of opioid overdose deaths for which benzodiazepines were also implicated increased from 18% to 31% 3
b) In a prospective cohort study performed in North Carolina, overdose deaths in patients who were dispensed both opioids and benzodiazepines were 10-fold greater than those dispensed opioids alone (7 per 10,000 person-years vs 0.7 per 10,000 person-years). A case-cohort study in the Veterans Health Administration demonstrated that patients taking opioids with a history of or current benzodiazepine prescription had an increased risk of death due to overdose compared with patients taking opioids without a history of benzodiazepine prescription, risk increased 2.33- to 3.86-fold in patient with current or historical prescriptions for benzodiazepines. As daily benzodiazepine doses increased, risk of death due to drug overdose increased as well 3
Common questions
Can I take Butorphanol Injection and Perampanel together?
Increased risk of respiratory and CNS depression Always confirm with your pharmacist or prescriber before making any change.
How serious is the Butorphanol Injection and Perampanel interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Butorphanol Injection or Perampanel need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (3)
- Product Information: Butorphanol tartrate nasal spray, butorphanol tartrate nasal spray. Mylan Pharmaceuticals Inc (per DailyMed), Morgantown, WV, 2016. DailyMed
- Product Information: Butorphanol tartrate intramuscular injection, intravenous injection, butorphanol tartrate intramuscular injection, intravenous injection. Hospira Inc (per DailyMed), Lake Forest, IL, 2016.
- US Food and Drug Administration (FDA): Drug Safety Communications: FDA warns about serious risks and death when combining opioid pain or cough medicines with benzodiazepines; requires its strongest warning. US Food and Drug Administration (FDA). Silver Spring, MD. 2016.
Keep reading about Perampanel
Keep reading about Butorphanol Injection
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