What the FDA labels say about taking them together
Diazepam and fentanyl
Fentanyl's FDA label of March 6, 2026 names diazepam in its drug interactions section; diazepam's label does not name fentanyl itself but warns about its class (Opioids (opioid agonists)). The fentanyl label: “The concomitant use of Fentanyl Citrate Injection with CNS depressants may result in decreased pulmonary artery pressure and may cause hypotension. …”
Check it at the source: the diazepam FDA label on DailyMed (effective August 11, 2026, Waylis Therapuetics LLC); the fentanyl FDA label on DailyMed (effective March 6, 2026, Hikma Pharmaceuticals USA Inc.).
What does the diazepam label say about fentanyl?
Diazepam's label does not name fentanyl itself; it warns about its class (Opioids (opioid agonists)):
Diazepam label, boxed warningABUSE, MISUSE, AND ADDICTION; and DEPENDENCE AND WITHDRAWAL REACTIONS See full prescribing information for complete boxed warning Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death. ( 5.1 , 7.1 ) The use of benzodiazepines, including VALTOCO, exposes users to risks of abuse, misuse, and addiction, which can lead to overdose or death.
Diazepam label, boxed warningABUSE, MISUSE, AND ADDICTION; and DEPENDENCE AND WITHDRAWAL REACTIONS Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death.
Source: FDA drug label (Valium), Waylis Therapuetics LLC, effective August 11, 2026 (SPL set 260e2041-2bb3-482f-850e-b5d47a7bdbe6), via openFDA; the full label on DailyMed
What does the fentanyl label say about diazepam?
Fentanyl label, drug interactionsBenzodiazepines and Other Central Nervous System (CNS) Depressants Clinical Impact: The concomitant use of Fentanyl Citrate Injection with CNS depressants may result in decreased pulmonary artery pressure and may cause hypotension. Even small dosages of diazepam may cause cardiovascular depression when added to high dose or anesthetic dosages of Fentanyl Citrate Injection. … Intervention: As postoperative analgesia, start with a lower dose of Fentanyl Citrate Injection and monitor patients for signs of respiratory depression, sedation, and hypotension. Fluids or other measures to counter hypotension should be available [see ]. …
Fentanyl label, warnings and precautionsWhen high dose or anesthetic dosages of Fentanyl Citrate Injection are employed, even relatively small dosages of diazepam may cause cardiovascular depression.
Source: FDA drug label (Fentanyl Citrate), Hikma Pharmaceuticals USA Inc., effective March 6, 2026 (SPL set ce5db1c2-feb1-4ad2-847a-d02e865bd47e), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Diazepam | Fentanyl | |
|---|---|---|
| Labeled for | Anxiety, Muscle spasms and spasticity | Pain |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.0283 per tablet 10 mg tablet | $1.79 per mL 100 mcg/2 mL vial |
| Shortage now | No current entry | In shortage |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once