Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
OXYCONTIN vs ZOHYDRO 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.
Zohydro ER is a pure opioid agonist with relative selectivity for mu-opioid receptors, although it can interact with other opioid receptors at higher doses. Its primary therapeutic action is analgesia via binding to mu-opioid receptors in the central nervous system, leading to activation of descending inhibitory pathways and modulation of pain perception.
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)
Zohydro ER is indicated for the management of pain severe enough to require daily, around-the-clock, long-term opioid treatment and for which alternative treatment options are inadequate.
10 mg orally every 12 hours; titrate based on pain severity and prior opioid exposure.
Initial: 20 mg orally every 24 hours; titrate in increments of 10-20 mg every 3-7 days as needed; maximum dose 200 mg every 24 hours.
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.
Terminal elimination half-life is approximately 10.6 hours (range 8-17 hours) due to extended-release formulation; immediate-release hydromorphone half-life is 2-3 hours. Clinically, steady-state is achieved after 3-5 days of dosing.
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.
Hydrocodone is primarily metabolized by CYP3A4 and CYP2D6. CYP3A4 is the major enzyme responsible for N-demethylation to norhydrocodone, while CYP2D6 mediates O-demethylation to hydromorphone, a more potent opioid metabolite.
Primarily renal (90% as metabolites, 10% unchanged). Also biliary/fecal (10%).
Primarily renal excretion of hydromorphone-3-glucuronide (H3G, ~60%), unchanged hydromorphone (~15%), and other conjugates. Fecal excretion accounts for ~25%.
38-45%, primarily bound to albumin.
Approximately 20-30% bound to plasma proteins (albumin). Low binding minimizes drug interactions from protein displacement.
2.6-3.0 L/kg. Extensive tissue distribution, high Vd indicates penetration into peripheral tissues.
Volume of distribution (Vd) is approximately 3.5 L/kg (range 2-5 L/kg), indicating extensive tissue distribution beyond total body water.
Oral immediate-release: 60-87% (first-pass metabolism). Oral extended-release (Oxy Contin): 60-87% (similar). Intravenous: 100%.
Oral bioavailability is ~50% (range 40-60%) due to first-pass metabolism; extended-release formulation provides consistent absorption over 12 hours.
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 30-59 m L/min: Initiate at 50% of usual dose and titrate cautiously; GFR <30 m L/min: Not recommended due to accumulation of metabolites.
Child-Pugh Class A: no adjustment; Child-Pugh Class B: reduce dose by 50%; Child-Pugh Class C: avoid use.
Child-Pugh Class A: No adjustment; Child-Pugh Class B: Initiate at 50% of usual dose; Child-Pugh Class 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.
Not approved for pediatric patients; safety and efficacy not established.
Initiate at 5 mg orally every 12 hours; titrate cautiously; monitor for respiratory depression and constipation.
Initiate at 20 mg every 24 hours; titrate cautiously due to increased sensitivity and risk of respiratory depression.
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: 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.
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.
Addiction, Abuse, and Misuse,Life-Threatening Respiratory Depression,Neonatal Opioid Withdrawal Syndrome,Risks from Concomitant Use with Benzodiazepines or Other CNS Depressants,Adrenal Insufficiency,Severe Hypotension,Gastrointestinal Effects: Constipation and Risk of Obstruction,Seizures in Patients with Seizure Disorders,Avoidance of Rapid Withdrawal,Driving and Operating Machinery
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
Significant respiratory depression,Acute or severe bronchial asthma in an unmonitored setting or in absence of resuscitative equipment,Known or suspected gastrointestinal obstruction, including paralytic ileus,Hypersensitivity to hydrocodone or any other components of the product (e.g., anaphylaxis)
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.
Take on an empty stomach (1 hour before or 2 hours after a meal) to prevent dose dumping. Avoid alcohol in any form (including medications containing alcohol, food prepared with alcohol, or alcoholic beverages) due to risk of rapid release and fatal overdose. Grapefruit juice may increase plasma hydrocodone levels; avoid concurrent use.
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.
ZOHYDRO ER contains hydrocodone, a Schedule II opioid. First trimester: Increased risk of neural tube defects (OR 2.2) and congenital heart defects (OR 1.8). Second and third trimesters: Chronic use may cause fetal opioid dependence, neonatal abstinence syndrome (NAS), and preterm birth. Avoid use during labor due to risk of neonatal respiratory depression.
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).
Hydrocodone is excreted in breast milk with a relative infant dose of approximately 2-3% of maternal weight-adjusted dose. M/P ratio is approximately 1.0. Use with caution; monitor infant for drowsiness, respiratory depression, and poor feeding. Higher risk in CYP2D6 ultra-rapid metabolizers.
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.
Pregnancy may alter hydrocodone pharmacokinetics. Increased clearance and volume of distribution in late pregnancy may require dose increases. However, due to teratogenicity and NAS risk, use only if benefits outweigh risks, with smallest effective dose and shortest duration. Avoid in third trimester; taper if possible before delivery.
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.
Zohydro ER is an extended-release hydrocodone formulation that should be taken on an empty stomach (1 hour before or 2 hours after a meal) to avoid dose dumping. It is not bioequivalent to immediate-release hydrocodone; use caution when converting. Due to high alcohol content in the capsule (10% ethanol), patients with alcohol intolerance or liver disease may experience adverse effects. Prescribe only for opioid-tolerant patients requiring around-the-clock analgesia. Avoid in patients with significant respiratory depression, paralytic ileus, or MAOI use within 14 days.
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.
Swallow capsules whole; do not crush, chew, or dissolve as this can cause fatal overdose.,Do not consume alcohol while taking Zohydro ER; the capsule contains alcohol and additional alcohol may lead to rapid release and overdose.,Avoid grapefruit juice as it may increase hydrocodone levels.,Take exactly as prescribed; do not increase dose or frequency without consulting your doctor.,Do not stop abruptly; withdrawal symptoms may occur. Taper under medical supervision.,Store securely out of reach of children and pets; dispose of unused medication via take-back programs.,Report severe drowsiness, slowed breathing, or difficulty breathing to a healthcare provider immediately.,Avoid driving or operating heavy machinery until you know how the medication affects you.
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 ZOHYDRO 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.. ZOHYDRO ER is a Opioid Analgesic that works by Zohydro ER is a pure opioid agonist with relative selectivity for mu-opioid receptors, although it can interact with other opioid receptors at higher doses. Its primary therapeutic action is analgesia via binding to mu-opioid receptors in the central nervous system, leading to activation of descending inhibitory pathways and modulation of pain perception.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between OXYCONTIN and ZOHYDRO ER depend on the specific clinical indication. These are both Opioid Analgesic agents 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 ZOHYDRO ER is: Initial: 20 mg orally every 24 hours; titrate in increments of 10-20 mg every 3-7 days as needed; maximum dose 200 mg every 24 hours.. 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 ZOHYDRO 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. ZOHYDRO ER is classified as Category C. ZOHYDRO ER contains hydrocodone, a Schedule II opioid. First trimester: Increased risk of neural tube defects (OR 2.2) and congenital heart defects (OR 1.8). Second and third trime. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.