Oxycodone (OxyContin, Percocet, Roxicodone) is a Schedule II opioid analgesic used for moderate-to-severe pain that requires around-the-clock or as-needed treatment. It acts as a full agonist at mu-opioid receptors in the brain and spinal cord, reducing pain perception and emotional response to pain. It carries a high risk of dependence, addiction, and overdose — respiratory depression is the primary cause of opioid-related death. A critical public safety concern: counterfeit pills mimicking oxycodone tablets frequently contain illicitly manufactured fentanyl and have caused tens of thousands of overdose deaths.
Oxycodone
Uses & FDA Indications
Oxycodone is FDA-approved for the management of pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate. Immediate-release formulations are used for both around-the-clock and as-needed pain management. Extended-release oxycodone (OxyContin) is indicated only for pain requiring continuous, long-term opioid treatment — it is not intended for as-needed analgesia.
Common clinical uses include post-surgical pain, cancer-related pain, injury-related pain, and chronic pain conditions where other analgesics have been insufficient. Percocet, which combines oxycodone with acetaminophen, is widely prescribed for acute moderate-to-severe pain.
Prescribers must follow REMS (Risk Evaluation and Mitigation Strategy) requirements for extended-release opioids, which mandate patient counseling on safe use, storage, and disposal. Oxycodone prescriptions require a written or electronic prescription — telephone prescriptions are not permitted under Schedule II regulations.
BLACK BOX WARNING: Oxycodone carries FDA black box warnings for addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion (especially by children); neonatal opioid withdrawal syndrome with use during pregnancy; and dangerous interactions with benzodiazepines and other CNS depressants.
How It Works
Oxycodone is a semisynthetic opioid derived from thebaine, an alkaloid found in opium. It functions as a full agonist at mu-opioid receptors (MOR) throughout the central and peripheral nervous system. Activation of mu receptors in the brain and spinal cord produces analgesia by inhibiting ascending pain pathways, altering pain perception in the cortex, and reducing emotional response to pain via limbic system effects.
Oxycodone also binds to kappa-opioid receptors, contributing to its sedative and dysphoric properties. Peripheral opioid receptor activation accounts for some of its gastrointestinal effects — slowing gut motility, reducing peristalsis, and causing constipation.
Oxycodone is approximately 1.5 times more potent than oral morphine on a milligram basis. It is metabolized by CYP3A4 (to noroxycodone) and CYP2D6 (to oxymorphone, its active metabolite). CYP2D6 poor metabolizers produce less oxymorphone, which may affect analgesic response, while CYP2D6 ultra-rapid metabolizers may experience exaggerated effects.
Side Effects
Common
- Constipation — nearly universal with opioid use; does not develop tolerance like other opioid side effects; requires proactive bowel management
- Nausea and vomiting — common especially with initiation; often improves over days to weeks
- Sedation and drowsiness — impairs driving and cognitive function
- Dizziness and lightheadedness
- Pruritus (itching) — especially with neuraxial administration
- Dry mouth
- Miosis (pinpoint pupils) — a reliable pharmacodynamic marker of opioid effect
Serious
- Respiratory depression — the most dangerous opioid effect; risk increases with high doses, CNS depressant combinations, sleep apnea, or opioid-naive patients
- Opioid use disorder (OUD) — physical dependence and addiction can develop; risk factors include personal or family history of substance use disorder, mental health comorbidities, and younger age
- Opioid-induced hyperalgesia — paradoxical increased pain sensitivity with long-term opioid exposure
- Hypogonadism and hormonal effects — chronic opioid use suppresses the hypothalamic-pituitary-gonadal axis, reducing testosterone and estrogen, contributing to decreased libido, fatigue, and bone loss
- Adrenal insufficiency — rare but recognized complication of prolonged opioid use
- Overdose and death — particularly when combined with benzodiazepines, alcohol, or in the presence of counterfeit pills containing fentanyl
Drug Interactions
| Drug / Class | Interaction | Clinical Significance |
|---|---|---|
| Benzodiazepines (alprazolam, diazepam, clonazepam) | Synergistic CNS and respiratory depression. The opioid-benzodiazepine combination accounts for a large proportion of opioid overdose deaths in the US. | Critically High — FDA black box warning; avoid concurrent use when possible; if necessary, use lowest effective doses |
| Alcohol and CNS Depressants | Additive respiratory depression and sedation. Alcohol also disrupts the extended-release mechanism of OxyContin if consumed concurrently. | High — absolute contraindication with extended-release oxycodone |
| CYP3A4 Inhibitors (ketoconazole, ritonavir, clarithromycin, grapefruit) | Reduce oxycodone metabolism, dramatically increasing plasma levels and overdose risk. | High — reduce oxycodone dose and monitor closely; avoid grapefruit juice |
| CYP3A4 Inducers (rifampin, carbamazepine, St. John's Wort) | Accelerate oxycodone metabolism, potentially reducing efficacy and precipitating withdrawal in dependent patients. | Moderate-High — may need dose adjustment; monitor for withdrawal or inadequate analgesia |
| MAO Inhibitors (phenelzine, selegiline, linezolid) | Risk of serotonin syndrome and severe opioid toxicity. Contraindicated concurrently or within 14 days of MAOI use. | Critically High — contraindicated |
| Gabapentinoids (gabapentin, pregabalin) | Combination substantially increases respiratory depression and overdose risk beyond either agent alone. | High — avoid combination; if required, monitor respiratory status carefully |
Warnings & Contraindications
Contraindications
- Significant respiratory depression (without monitoring and resuscitative equipment)
- Acute or severe bronchial asthma in an unmonitored setting
- Known or suspected gastrointestinal obstruction, including paralytic ileus
- Hypersensitivity to oxycodone or any formulation component
- Concurrent use of MAO inhibitors or use within 14 days
Counterfeit Pill Epidemic
Law enforcement and public health agencies have documented a crisis-level influx of counterfeit prescription pills — particularly those mimicking oxycodone 30 mg tablets (small blue pills with M30 imprint) — that contain illicitly manufactured fentanyl (IMF) or fentanyl analogs. The DEA reports that approximately 6 in 10 counterfeit pills seized contain a potentially lethal dose of fentanyl. These pills are indistinguishable from genuine pharmaceutical tablets to the naked eye. Oxycodone tablets obtained from any source other than a licensed pharmacy filling a valid prescription should be treated as potentially life-threatening.
Physical Dependence and Withdrawal
Physical dependence develops with regular oxycodone use and is not the same as addiction, but it does mean that abrupt discontinuation will cause withdrawal. Opioid withdrawal is intensely uncomfortable — symptoms include severe anxiety, muscle aches, insomnia, diaphoresis, diarrhea, nausea, and vomiting — but is rarely life-threatening in otherwise healthy adults. Oxycodone should always be tapered gradually under medical supervision when discontinuing after prolonged use.
Risk in Special Populations
Elderly patients have reduced opioid clearance and are more susceptible to respiratory depression and falls. Patients with sleep apnea, obesity hypoventilation, or chronic pulmonary disease are at markedly elevated risk of respiratory depression. Oxycodone should not be used during pregnancy except under careful risk-benefit assessment, as neonatal opioid withdrawal syndrome will occur in newborns exposed in utero.
Check for dangerous interactions with oxycodone and other medications.
Check Drug Interactions →Frequently Asked Questions
What is the difference between oxycodone and OxyContin?
Oxycodone is the active drug molecule. OxyContin is Purdue Pharma's brand name for an extended-release (ER) formulation of oxycodone designed to deliver the medication over 12 hours. Roxicodone and generic immediate-release tablets deliver oxycodone rapidly with a shorter duration. Percocet is oxycodone combined with acetaminophen (325 mg APAP) in immediate-release form. All contain oxycodone as the active opioid, but their release characteristics, duration of action, and combination ingredients differ.
How dangerous is oxycodone overdose?
Oxycodone overdose is life-threatening. The classic overdose triad is pinpoint pupils, unconsciousness, and respiratory depression — slowed or stopped breathing is the primary cause of death. Overdose risk increases dramatically when oxycodone is combined with other CNS depressants such as benzodiazepines, alcohol, or gabapentin. Naloxone (Narcan) reverses opioid overdose and should be kept available by anyone taking prescription opioids or living with someone who does. Emergency services should always be called — naloxone's effect wears off before many opioids do.
Are counterfeit oxycodone pills dangerous?
Counterfeit oxycodone pills are extremely dangerous. The DEA has documented a widespread counterfeit pill epidemic in which pills pressed to look identical to legitimate oxycodone tablets (including the imprint, color, and size) contain illicitly manufactured fentanyl or other synthetic opioids. Because fentanyl is approximately 100 times more potent than morphine, a counterfeit pill with a non-uniform fentanyl distribution can deliver a lethal dose. Pills obtained outside a licensed pharmacy — through social contacts, online markets, or street sources — carry a high probability of being counterfeit and should never be ingested.