Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
OXYCONTIN vs ADZENYS ER
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Oxycodone is a full opioid agonist with relative selectivity for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of oxycodone is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia with oxycodone. Clinically, dosage is titrated to provide adequate analgesia and may be limited by adverse reactions, including respiratory and CNS depression.
ADZENYS ER is a central nervous system (CNS) stimulant that blocks the reuptake of norepinephrine and dopamine into presynaptic neurons, increasing their concentrations in the synaptic cleft.
Management of pain severe enough to require daily, around-the-clock, long-term opioid treatment and for which alternative treatment options are inadequate,Off-label: Treatment of opioid dependence (as part of substitution therapy)
Attention Deficit Hyperactivity Disorder (ADHD)
10 mg orally every 12 hours; titrate based on pain severity and prior opioid exposure.
Adults: Initial 5-10 mg orally once daily; titrate in 5-10 mg increments weekly to optimal response; max 60 mg/day.
4.5-5.0 hours (immediate-release); controlled-release OXYCONTIN has an apparent half-life of 4.5-8.7 hours. Terminal half-life is ~3.5-4 hours for immediate-release, reflecting context-sensitive elimination.
6-8 hours in adults; in children 3-6 hours, requiring twice-daily dosing for sustained effect
Oxycodone is metabolized primarily via CYP3A4 to noroxycodone (major metabolite) and via CYP2D6 to oxymorphone (minor metabolite). Both metabolites are active, with oxymorphone having higher potency. Oxycodone and its metabolites are conjugated and excreted in urine.
Metabolized primarily by hepatic esterases and cytochrome P450 (CYP) enzymes, including CYP2D6.
Primarily renal (90% as metabolites, 10% unchanged). Also biliary/fecal (10%).
70% renal (30% unchanged, 40% as metabolites), 30% fecal/biliary
38-45%, primarily bound to albumin.
97% bound to albumin and α1-acid glycoprotein
2.6-3.0 L/kg. Extensive tissue distribution, high Vd indicates penetration into peripheral tissues.
4.6-6.8 L/kg, indicating extensive tissue distribution, particularly in brain and adipose tissue
Oral immediate-release: 60-87% (first-pass metabolism). Oral extended-release (Oxy Contin): 60-87% (similar). Intravenous: 100%.
Oral: 95% ± 10%; rectal: 80% ± 15%
Cr Cl 30-60 m L/min: reduce dose by 25%; Cr Cl <30 m L/min: reduce dose by 50% and administer every 12 hours; hemodialysis: avoid use.
GFR 30-89 m L/min: No adjustment. GFR <30 m L/min: Not recommended.
Child-Pugh Class A: no adjustment; Child-Pugh Class B: reduce dose by 50%; Child-Pugh Class C: avoid use.
Child-Pugh A: No adjustment. Child-Pugh B: Reduce dose by 50%. Child-Pugh C: Not recommended.
Not approved for pediatric patients <18 years; for children ≥11 years (opioid-tolerant): 0.2 mg/kg orally every 12 hours, titrate; maximum single dose 10 mg.
Children ≥6 years: Initial 5-10 mg orally once daily; titrate weekly by 5-10 mg; max 1 mg/kg/day or 60 mg/day, whichever is lower.
Initiate at 5 mg orally every 12 hours; titrate cautiously; monitor for respiratory depression and constipation.
Initiate at 5 mg once daily; titrate cautiously; monitor for cardiovascular effects and insomnia.
WARNING: ADDICTION, ABUSE, AND MISUSE; LIFE-THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL INGESTION; NEONATAL OPIOID WITHDRAWAL SYNDROME; and RISKS FROM CONCOMITANT USE WITH BENZODIAZEPINES OR OTHER CNS DEPRESSANTS
WARNING: ABUSE AND DEPENDENCE. CNS stimulants, including ADZENYS ER, have a high potential for abuse and dependence. Assess the risk of abuse prior to prescribing and monitor for signs of abuse and dependence while on therapy.
Addiction, abuse, and misuse: Oxy Contin exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess each patient's risk prior to prescribing, and monitor all patients regularly for the development of these behaviors or conditions.,Life-threatening respiratory depression: Serious, life-threatening, or fatal respiratory depression may occur. Monitor for respiratory depression, especially during initiation of therapy or following a dose increase. Instruct patients to swallow tablets whole; crushing, chewing, or dissolving can cause rapid release and absorption of a potentially fatal dose.,Accidental ingestion: Accidental ingestion of even one dose of Oxy Contin, especially by children, can result in a fatal overdose of oxycodone.,Neonatal opioid withdrawal syndrome: Prolonged use of Oxy Contin during pregnancy can result in withdrawal in the neonate. Neonatal opioid withdrawal syndrome, unlike opioid withdrawal in adults, may be life-threatening if not recognized and treated.,Risks from concomitant use with benzodiazepines or other CNS depressants: Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing for use in patients for whom alternative treatment options are inadequate.
Serious cardiovascular events: Sudden death, stroke, and myocardial infarction have been reported in patients with pre-existing cardiac abnormalities.,Blood pressure and heart rate increase: Monitor regularly.,Psychiatric adverse reactions: May precipitate or exacerbate psychosis or mania.,Long-term suppression of growth in pediatric patients: Monitor height and weight.,Seizures: May lower seizure threshold in patients with history of seizures.,Peripheral vasculopathy: Including Raynaud's phenomenon.
Significant respiratory depression,Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment,Known or suspected gastrointestinal obstruction, including paralytic ileus,Hypersensitivity (e.g., anaphylaxis) to oxycodone or any other components of the product
Known hypersensitivity to amphetamines or other components of ADZENYS ER,Concurrent use of monoamine oxidase inhibitors (MAOIs) or within 14 days of discontinuing an MAOI,Agitated states,History of drug abuse,Cardiovascular disease including hypertension, arteriosclerosis, hyperthyroidism, glaucoma
Avoid alcohol, which can increase oxycodone absorption and central nervous system depression. Grapefruit juice may alter oxycodone metabolism; limit or avoid consumption. No specific food restrictions, but high-fat meals may slow absorption slightly; take with or without food consistently.
High-fat meals can significantly delay and reduce the absorption of Adzenys ER; the time to peak concentration (Tmax) may be prolonged by approximately 1 hour and peak concentration (Cmax) reduced by about 38%. It is recommended to take Adzenys ER on an empty stomach (at least 1 hour before or 2 hours after a meal) to ensure consistent effect. Avoid alcohol while taking this medication, as it may increase the risk of cardiovascular side effects and impair judgment. No other specific food interactions are known, but patients should maintain a balanced diet to manage potential appetite suppression common with amphetamines.
FDA Pregnancy Category C prior to 2020; no adequate studies in pregnant women. First trimester: Limited data suggest possible increased risk of neural tube defects (1.8-fold) and oral clefts (1.5-fold) with opioid use, but confounded by underlying conditions. Second and third trimesters: Chronic use may cause fetal opioid dependence and neonatal abstinence syndrome (NAS); maternal withdrawal may precipitate preterm labor. Avoid prolonged use near term due to risk of neonatal respiratory depression.
First trimester: Inadequate human data; animal studies show no evidence of teratogenicity at clinically relevant doses. Second and third trimesters: Chronic use may lead to neonatal withdrawal syndrome (hyperactivity, irritability, poor feeding) and reduced fetal growth. Avoid in first trimester unless benefit outweighs risk; use lowest effective dose in later trimesters.
Oxycodone is excreted into breast milk; relative infant dose is approximately 2.7–8.8% of maternal weight-adjusted dose. M/P ratio unknown. Monitor infant for sedation, respiratory depression, and poor feeding. American Academy of Pediatrics considers oxycodone compatible with breastfeeding with caution; avoid rapid accumulation in mothers with impaired metabolism (CYP2D6 poor metabolizers).
Excreted in breast milk; M/P ratio approximately 2.6. Irritability and weight loss reported in nursing infants. Not recommended unless benefit outweighs risk.
Pregnancy increases oxycodone clearance by 1.3- to 2.5-fold due to enhanced hepatic metabolism (CYP3A4 and CYP2D6 induction) and increased renal blood flow. Dose adjustments may be necessary to maintain analgesia; clinical monitoring for pain control and withdrawal symptoms is essential. Titrate to effect; avoid abrupt discontinuation. Postpartum clearance returns to baseline over 1-2 weeks.
Clearance increased by approximately 30% in third trimester; may require dose escalation. Postpartum dose reduction may be needed to avoid toxicity. Individual titration based on clinical response and tolerability.
Oxy Contin is an extended-release formulation of oxycodone, indicated for around-the-clock pain management. Do not crush, chew, or break tablets, as this can lead to rapid release and fatal overdose. Use with caution in patients with respiratory compromise, head injury, or increased intracranial pressure. Monitor for signs of misuse, abuse, or addiction. Abrupt discontinuation may precipitate withdrawal; taper dose gradually. Constipation is common; consider prophylactic laxatives. Contraindicated in severe asthma, paralytic ileus, or hypersensitivity.
Adzenys ER is an extended-release oral suspension of amphetamine (mixed salts) for ADHD. It provides a rapid onset (within 1 hour) and sustained effect over 10-12 hours. The suspension must be shaken vigorously for at least 10 seconds before each use. Dose titration should be guided by efficacy and tolerability, starting at 6.3 mg once daily in the morning for children 6-12 years. Avoid administration with high-fat meals as they may delay absorption (Cmax reduced by ~38%). Monitor for cardiovascular effects: heart rate, blood pressure, and potential for sudden death in patients with structural cardiac abnormalities. Use cautiously in patients with pyschosis, bipolar disorder, hypertension, hyperthyroidism, glaucoma, or history of drug abuse. Discontinue if agitation, aggression, or manic symptoms emerge. Drug holidays (weekend or holiday breaks) may be considered to assess need and reduce tolerance.
Take Oxy Contin exactly as prescribed, usually every 12 hours. Do not take more or less than directed.,Swallow the tablet whole with water. Do not crush, chew, or break the tablet, as this can cause a dangerous overdose.,Avoid alcohol and other central nervous system depressants (e.g., benzodiazepines, sedatives) as they increase the risk of severe sedation, respiratory depression, and death.,Do not stop taking Oxy Contin suddenly; ask your doctor how to safely discontinue the medication to avoid withdrawal symptoms.,Common side effects include constipation, nausea, drowsiness, and dizziness. Contact your doctor if you experience severe constipation, difficulty breathing, or signs of allergic reaction.,Store Oxy Contin in a secure place out of sight and reach of children and pets. Dispose of unused medication via a drug take-back program.,Do not drive or operate heavy machinery until you know how Oxy Contin affects you.,Inform all healthcare providers that you are taking Oxy Contin, especially before surgery or emergency treatment.
Take Adzenys ER exactly as prescribed, once daily in the morning; do not take in the afternoon or evening to avoid insomnia.,Shake the bottle vigorously for at least 10 seconds before each use; use the provided oral syringe to measure the correct dose.,Do not mix the medication with food or liquids; take it directly from the syringe.,Avoid taking with high-fat meals, as they may delay and reduce the drug's effect; take on an empty stomach if possible.,Store at room temperature (20-25°C); protect from light and moisture. Discard any unused portion after 30 days of opening.,Notify your doctor immediately if you experience chest pain, shortness of breath, fainting, or palpitations.,This medication has a high potential for abuse; do not share it with others and keep in a safe place.,Inform your doctor about all other medications, including OTC drugs and supplements, especially MAOIs (avoid within 14 days), antihypertensives, and SSRIs.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about OXYCONTIN vs ADZENYS ER, answered by our medical review team.
OXYCONTIN is a Opioid Analgesic that works by Oxycodone is a full opioid agonist with relative selectivity for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of oxycodone is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia with oxycodone. Clinically, dosage is titrated to provide adequate analgesia and may be limited by adverse reactions, including respiratory and CNS depression.. ADZENYS ER is a CNS Stimulant that works by ADZENYS ER is a central nervous system (CNS) stimulant that blocks the reuptake of norepinephrine and dopamine into presynaptic neurons, increasing their concentrations in the synaptic cleft.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between OXYCONTIN and ADZENYS ER depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of OXYCONTIN is: 10 mg orally every 12 hours; titrate based on pain severity and prior opioid exposure.. The standard adult dose of ADZENYS ER is: Adults: Initial 5-10 mg orally once daily; titrate in 5-10 mg increments weekly to optimal response; max 60 mg/day.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between OXYCONTIN and ADZENYS ER in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. OXYCONTIN is classified as Category C. FDA Pregnancy Category C prior to 2020; no adequate studies in pregnant women. First trimester: Limited data suggest possible increased risk of neural tube defects (1.8-fold) and o. ADZENYS ER is classified as Category C. First trimester: Inadequate human data; animal studies show no evidence of teratogenicity at clinically relevant doses. Second and third trimesters: Chronic use may lead to neonata. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.