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fentanyl vs oxycodone

Side-by-side comparison of fentanyl and oxycodone Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

Drug Class
fentanyl Opioid Analgesic
oxycodone Opioid Analgesic
Type
fentanyl Prescription
oxycodone Prescription
Summary
fentanyl

Fentanyl Citrate Injection is a strong opioid pain medicine. It is used to provide short-term pain relief, often during and after surgery.

oxycodone

Oxycodone is a strong pain medicine. It is used to treat severe pain that is not helped by other treatments.

What It Treats
fentanyl

Fentanyl Citrate Injection is used to manage pain during and after surgery. It can be used alone or with other medicines during general or regional anesthesia. It may also be used with oxygen for high-risk patients during certain surgeries.

oxycodone

Oxycodone is used to manage severe pain. It is for pain that requires an opioid medicine. You should only use it when other pain treatments are not enough. Talk to your doctor about other options if possible.

How It Works
fentanyl

Fentanyl is an opioid that works by binding to receptors in the brain and spinal cord. This binding decreases the feeling of pain. It can also cause sleepiness and slow breathing.

oxycodone

Oxycodone works by changing how your brain and nervous system respond to pain. It attaches to certain receptors in the brain. This helps to block pain signals and reduce pain.

Common Side Effects
fentanyl
  • Nausea
  • Vomiting
  • Dizziness
  • Blurred vision
oxycodone
  • Feeling sick to your stomach
  • Constipation
  • Throwing up
  • Headache
  • Itching
FAERS Reports
fentanyl
  • Misuse of drugs 10,453
  • Pain 7,248
  • Drug addiction 6,027
  • Harmful effect from drugs 5,847
  • Taking too much of a drug 5,722
oxycodone
  • Addiction to the drug 27,480
  • Pain 26,410
  • Death 19,598
  • Taking too much of the drug 19,081
  • Harmful effects from different substances 16,254
Serious Warnings
fentanyl

Fentanyl Citrate Injection can cause serious and life-threatening risks: * Addiction, abuse, and misuse can lead to overdose and death. Your doctor will assess your risk before prescribing and monitor you regularly. * Life-threatening respiratory depression (slowed or stopped breathing) can occur, especially when starting the medicine or after a dose increase. Proper dosing is essential. * Taking fentanyl with benzodiazepines (like Valium or Xanax) or other CNS depressants (including alcohol) can cause severe sleepiness, slowed breathing, coma, and death. This combination should be avoided unless there are no other options. * Using fentanyl with certain other medicines (CYP3A4 inhibitors or inducers) can change the amount of fentanyl in your blood, leading to dangerous side effects or withdrawal symptoms. Your doctor will monitor you closely if these medicines are used together.

oxycodone

Oxycodone can cause serious, life-threatening risks: * Addiction, abuse, and misuse can lead to overdose and death. Your doctor will check your risk before prescribing and during treatment. * It can cause very slow or stopped breathing, especially when you start taking it or after a dose increase. * If a child accidentally takes even one dose, it can cause a fatal overdose. * Taking it with benzodiazepines (like Xanax) or other depressants (like alcohol) can cause sleepiness, slowed breathing, coma, and death. * Using oxycodone for a long time during pregnancy can cause withdrawal symptoms in the newborn. * Taking oxycodone with certain other medicines can cause dangerous side effects.

Pregnancy
fentanyl

Using fentanyl for a long time during pregnancy can cause withdrawal symptoms in the newborn. Fentanyl is not recommended during labor or delivery because it can cause breathing problems in the baby.

oxycodone

Using oxycodone for a long time during pregnancy can cause withdrawal symptoms in the baby after birth. Talk to your doctor about the risks if you are pregnant or plan to become pregnant. Oxycodone is not recommended during labor, as it can cause breathing problems in the newborn.

Also Compare — Nearby Drugs

How to Read This fentanyl vs oxycodone Comparison

fentanyl is classified in the Opioid Analgesic drug class, while oxycodone sits within the Opioid Analgesic class. Because both drugs share the same classification, they are often considered interchangeable in theory — but clinical outcomes rarely track that cleanly. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, fentanyl has 35,297 submissions while oxycodone has 108,823. Those figures reflect cumulative reporting volume — not per-patient risk — so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between fentanyl and oxycodone — always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.