Hydromorphone

Pronunciation: hy-droh-MOR-fone.

Generic name
hydromorphone hydrochloride
Drug class
Opioid (mu-receptor) agonist -- a semi-synthetic hydrogenated ketone derivative of morphine
Form
Immediate-release tablet and oral solution (Dilaudid, US); injection, including a high-potency (HP) strength for opioid-tolerant patients (Dilaudid/Dilaudid-HP); extended-release tablet (generic, US; brand Exalgo discontinued); controlled-release capsule (Hydromorph Contin, Canada); sustained-release capsule (Palladone SR, UK); prolonged-release tablet with OROS delivery (Jurnista, EU -- discontinued in Australia)
Route
Oral (immediate-release tablet or oral solution, or extended/controlled-release tablet/capsule) or injection (subcutaneous, intramuscular, or intravenous), depending on the specific formulation
Legal status
Controlled/restricted prescription medicine in all markets reviewed where currently marketed (e.g. Schedule 8 in Australia, Schedule II in the US); extended-release formulations additionally require prescriber/patient education under a restricted REMS program in the US

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia

Australia: Dilaudid (immediate-release tablets) (7), Dilaudid / Dilaudid-HP (injection) (7), Jurnista (prolonged-release tablets) -- DISCONTINUED, not currently available (7) · Full directory

What hydromorphone hydrochloride is and how it works

Hydromorphone is a potent, controlled prescription opioid pain medicine, chemically related to morphine, used for pain severe enough to require an opioid analgesic when other treatment options are inadequate. It is available as immediate-release oral tablets or solution and as an injection for shorter-term or acute pain, and as extended/controlled-release oral tablets or capsules for patients already tolerant to opioids who need continuous, around-the-clock pain control. (1) (3)

Hydromorphone carries a genuine FDA boxed warning covering addiction, abuse, and misuse risk; life-threatening respiratory depression, especially when starting treatment or after a dose increase; a serious risk of fatal overdose from accidental exposure to even a single dose, especially in children; and Neonatal Opioid Withdrawal Syndrome with extended use in pregnancy. Two further specific points apply to particular formulations: the oral solution carries its own warning about mg/mL dosing-error risk between different concentrations, and extended-release tablets must be swallowed whole and are intended only for patients who are already opioid-tolerant. Hydromorphone should only be used exactly as directed by the prescriber managing your care.

Mechanism of action: how hydromorphone hydrochloride works

Hydromorphone is a semi-synthetic opioid, a hydrogenated ketone of morphine, acting primarily as a full agonist at the mu-opioid receptor. Unlike some other opioids, hydromorphone is not significantly metabolised via cytochrome P450 enzymes (including CYP3A4) and is not expected to inhibit CYP450 substrates, per the UK SmPC reviewed -- a genuine pharmacological difference from opioids such as oxycodone or buprenorphine that are CYP3A4 substrates. (4) (1)

What hydromorphone hydrochloride is used for

Management of moderate to severe acute pain

Immediate-release tablets, oral solution, and injectable formulations are used for pain severe enough to require an opioid analgesic, when alternative treatments (including non-opioid options) are inadequate -- for example after surgery, for injury-related pain, or for cancer pain. (1) (2)

Management of severe and persistent pain requiring continuous opioid treatment (opioid-tolerant patients)

Extended-release, controlled-release, and prolonged-release formulations (e.g. Hydromorph Contin, Palladone SR, Jurnista where available) are used for severe, persistent pain needing round-the-clock opioid treatment for an extended period, in patients who are already opioid-tolerant. These are not approved for as-needed (prn) pain relief and are not intended for opioid-naive patients. (3) (6) (4)

Before taking hydromorphone hydrochloride

Do not take / not appropriate for

  • Do not use hydromorphone if you have significant respiratory depression, acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment available, or a known or suspected gastrointestinal obstruction including paralytic ileus. (United States) (1)
  • Do not use hydromorphone if you have a known serious allergic reaction to hydromorphone or its ingredients. (all countries) (1) (4)
  • Do not use Palladone/Palladone SR if you have severe COPD, severe bronchial asthma, paralytic ileus, acute abdomen, coma, hepatic impairment, or are taking an MAOI -- confirmed as contraindications in the UK source reviewed. (United Kingdom) (4)
  • Never break, chew, dissolve, or crush an extended-release/controlled-release hydromorphone tablet or capsule -- this releases a potentially fatal dose rapidly. These formulations are for opioid-tolerant patients only. (United States, Canada) (3) (6)

Tell your clinician about

  • Any history of substance use disorder or opioid misuse.
  • Any breathing problems, including sleep apnoea, asthma, or COPD.
  • Any liver or kidney problems.
  • Any history of head injury, increased pressure in the brain, or seizures.
  • Whether you are pregnant, plan to become pregnant, or are breastfeeding.
  • All other medicines and substances you take, especially benzodiazepines, other sedatives, alcohol, MAOIs, and serotonergic medicines.
(1) (4)

How to take hydromorphone hydrochloride

  • Use exactly as directed by your prescriber -- hydromorphone formulations differ significantly in strength and release profile, and following the wrong instructions for your specific product can be dangerous.
  • For oral solution: measure the dose carefully using the device provided; different oral-solution concentrations exist, and confusing mg with mL, or one concentration with another, has caused fatal overdoses.
  • For extended-release/controlled-release tablets or capsules: swallow whole; do not break, chew, dissolve, or crush; these are intended only for patients already tolerant to opioids.
  • For injection: administered by, or as directed by, a healthcare professional; a high-potency (HP) injection strength exists for opioid-tolerant patients only and must not be confused with standard strengths.
  • Never change your dose, switch formulations, or stop treatment on your own -- always work with your prescriber.
(1) (6) (4)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6) (7) (8)

Missed dose

Contact your prescriber for guidance if you miss a dose of an extended-release/controlled-release formulation -- do not take an extra dose or attempt to make up a missed dose yourself, given the serious overdose risk with opioid medicines.

Overdose

Seek emergency medical help immediately if an overdose is suspected -- signs include severe drowsiness, slow or stopped breathing, pinpoint pupils, limp muscles, cold/clammy skin, or unresponsiveness. Naloxone may be given by emergency responders to reverse the effects. Accidental exposure to even one dose, especially in a child, can be fatal -- seek emergency help immediately, even before symptoms appear. (1) (3)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Nausea and vomiting.

What to notice: Nausea and vomiting.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Constipation.

What to notice: Constipation.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Dizziness and somnolence (drowsiness).

What to notice: Dizziness and somnolence (drowsiness).

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Headache.

What to notice: Headache.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Dry mouth.

What to notice: Dry mouth.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Sweating.

What to notice: Sweating.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Serious warnings

Addiction, abuse, and misuse — boxed_warning

Symptoms: Not a symptom-based warning -- reflects the real risk that any opioid, including hydromorphone, can be misused, leading to overdose and death.

Action: Use exactly as prescribed; never share this medicine with anyone else; store it securely away from others, especially children and anyone with a history of substance use. (1)

Life-threatening respiratory depression — boxed_warning

Symptoms: Slow, shallow, or stopped breathing, extreme drowsiness, confusion, or unresponsiveness -- especially when starting treatment, after a dose increase, or when combined with alcohol, benzodiazepines, or other sedatives.

Action: Seek emergency medical help immediately. This risk is why hydromorphone must not be combined with benzodiazepines, alcohol, or other CNS depressants except under close prescriber supervision. (1)

Accidental exposure (especially in children) — boxed_warning

Symptoms: A child or another person who was not prescribed hydromorphone may show severe drowsiness, slowed breathing, or unresponsiveness after accidental ingestion of even one dose.

Action: Seek emergency medical help immediately. Store and dispose of all hydromorphone products securely and out of reach of children. (1)

Neonatal Opioid Withdrawal Syndrome — boxed_warning

Symptoms: In a newborn whose mother used hydromorphone for an extended period during pregnancy: irritability, poor feeding, tremor, or breathing difficulty, typically appearing hours to days after birth.

Action: This is a recognised, treatable condition when identified promptly by the neonatal care team; tell your prescriber and delivery team about hydromorphone use during pregnancy so the newborn can be monitored appropriately. (1) (4)

Dosing errors with oral solution (mg/mL confusion) — boxed_warning

Symptoms: Not applicable -- this reflects a real risk of measurement/prescribing error between different oral-solution concentrations, not a symptom.

Action: Ensure the exact concentration and dose (in both mg and mL) is confirmed with your pharmacist and prescriber every time; never assume two hydromorphone oral solutions of different strengths are interchangeable dose-for-dose. (1)

Rapid, potentially fatal release from a damaged extended-release tablet — boxed_warning

Symptoms: Not applicable -- this reflects a real risk of the tablet's release mechanism being bypassed by physical damage, not a symptom.

Action: Swallow extended-release tablets whole; never break, chew, dissolve, or crush them. These tablets are for opioid-tolerant patients only -- fatal respiratory depression could occur in someone who is not opioid-tolerant. (3)

Opioid Use Disorder with repeated use — high caution

Symptoms: Drug-seeking behaviour, using more than prescribed, or difficulty stopping despite wanting to.

Action: Discuss any concerns about dependence with your prescriber; do not stop or change your dose without medical guidance, since stopping abruptly can cause withdrawal. (4)

Interactions

  • Benzodiazepines and other CNS depressants (including alcohol): significantly increase the risk of profound sedation, respiratory depression, coma, and death when combined with hydromorphone. (1) (4)
  • Alcohol specifically: the UK SmPC reviewed states that concomitant alcohol use with Palladone SR capsules may increase undesirable effects and should be avoided. (4)
  • MAOIs: not recommended during treatment with an MAOI or within 14 days of stopping one, in the US source reviewed; contraindicated with Palladone/Palladone SR in the UK source reviewed. (1) (4)
  • Serotonergic medicines: may increase the risk of serotonin syndrome; if this is suspected, your prescriber will decide whether to discontinue hydromorphone. (1)
  • Mixed opioid agonist/antagonist medicines (e.g. pentazocine, nalbuphine, butorphanol): may reduce hydromorphone's effect and/or trigger withdrawal symptoms -- avoid combining unless directed by your prescriber. (1)
  • Real, verified absence: hydromorphone is not metabolised via cytochrome P450 enzymes (including CYP3A4) and is not expected to inhibit CYP450 substrates, per the UK SmPC reviewed -- a genuine difference from some other opioids that are CYP3A4 substrates. (4)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Not recommended in pregnancy per the UK source reviewed, due to impaired uterine contractility and the risk of Neonatal Opioid Withdrawal Syndrome with extended use. If opioid pain management is genuinely needed in pregnancy, this is a decision for the treating clinician, balancing risks and benefits individually. (1) (2) (3) (4) (5) (6) (7) (8)

Breastfeeding

Not recommended per the UK source reviewed, as hydromorphone is excreted into breast milk in low amounts and may cause respiratory depression in the infant. Discuss feeding options with your prescriber. (1) (2) (3) (4) (5) (6) (7) (8)

Children

Palladone/Palladone SR (UK) is authorised for severe cancer pain in children aged 12 years and above; other formulations reviewed do not specify a paediatric indication. Accidental exposure in a child of any age is a medical emergency regardless of formulation. (1) (2) (3) (4) (5) (6) (7) (8)

Elderly

Use with caution; elderly patients may be more sensitive to respiratory depression and sedation, and dose adjustment or closer monitoring may be needed. (1) (2) (3) (4) (5) (6) (7) (8)

Hepatic_impairment

The UK source reviewed contraindicates Palladone/Palladone SR in hepatic impairment; dose adjustment and caution are needed with any hydromorphone formulation in liver disease. (1) (2) (3) (4) (5) (6) (7) (8)

Renal_impairment

Specific dose guidance was not detailed in the sources reviewed for renal impairment; your prescriber will assess this individually, since opioid clearance can be affected by reduced kidney function. (1) (2) (3) (4) (5) (6) (7) (8)

Monitoring

Before starting

  • Assessment of respiratory function, including any sleep apnoea or lung disease
  • Assessment of opioid tolerance status before any extended-release/controlled-release formulation is prescribed
  • Liver and kidney function assessment where indicated
  • Review of all other medicines for benzodiazepine, CNS-depressant, MAOI, or serotonergic interactions

During treatment

  • Close monitoring for respiratory depression, especially at treatment initiation or after a dose increase.
  • Monitoring for signs of misuse, diversion, or ongoing substance use.
  • Periodic reassessment of continued need for opioid therapy.
(1) (6)

Storage

Store securely, out of reach of children and anyone other than the person prescribed the medicine, at room temperature away from heat and moisture. Dispose of unused medicine according to your pharmacist's instructions -- hydromorphone is a real overdose risk to children and pets even in small residual amounts.

Professional information

Clinician-facing context only, sourced from the current US FDA prescribing information (Dilaudid tablets/oral solution, Dilaudid injection, and generic extended-release tablets), the UK emc SmPC, and a Health Canada product monograph reviewed for this dossier; verify against the current full label before prescribing.

United States

Indication: Moderate to severe pain requiring an opioid analgesic (immediate-release, injection); severe and persistent pain in opioid-tolerant patients (extended-release)

Dose summary: Oral solution: 2.5-10 mL every 3-6 hours PRN. Tablets: 2-4 mg every 4-6 hours PRN. Injection: individualised, with a 10 mg/mL HP strength for opioid-tolerant patients only. Extended-release: individualised starting dose based on prior opioid requirement, opioid-tolerant patients only, REMS-restricted.

Renal context: Not specifically detailed in the sources reviewed; individualised assessment recommended. (1) (3)

United Kingdom

Indication: Severe cancer pain (adults and children 12+)

Dose summary: Palladone (immediate-release): 1.3-2.6 mg every 4 hours, individualised. Palladone SR (sustained-release): 2-24 mg strengths, dosed every 12 or 24 hours per product; 4 mg approximately equivalent to 30 mg oral morphine sulfate.

Renal context: Not specifically detailed in the sources reviewed. (4)

Canada

Indication: Severe and persistent pain requiring continuous opioid treatment

Dose summary: Hydromorph Contin (controlled-release): 3-30 mg strengths, releasing over approximately 12 hours; not for as-needed use.

Renal context: Not specifically detailed in the sources reviewed. (6)

Mechanism of action

Hepatic guidance

Use with caution in hepatic impairment; the UK source reviewed contraindicates Palladone/Palladone SR in hepatic impairment.

Overdose note

Manage with supportive care, respiratory support, and naloxone as needed; close monitoring is required given hydromorphone's potency, and repeat naloxone dosing or infusion may be needed depending on the formulation and amount involved. (4) (1)

Frequently asked questions

Is hydromorphone available in the US, UK, Europe, Canada, Australia, and New Zealand?

In five of these six regions, yes, in one or more formulations: the United States (Dilaudid tablets/oral solution/injection, and generic extended-release tablets), the United Kingdom (Palladone and Palladone SR), the European Union (Jurnista and other nationally authorised hydromorphone products), Canada (Hydromorph Contin and generic hydromorphone), and Australia (Dilaudid tablets and injection currently registered -- though the extended-release Jurnista product was discontinued there in 2023 and its registrations cancelled in 2024). New Zealand is a genuine exception: Medsafe's own Prescriber Update states that hydromorphone is not currently available in New Zealand. (1) (4) (5) (6) (7) (8)

Why does hydromorphone have a boxed warning?

Because, like other opioids, it carries a real risk of addiction, abuse, and misuse that can lead to overdose and death, along with a risk of life-threatening breathing problems (respiratory depression), especially when starting treatment or after a dose increase, or if combined with alcohol, benzodiazepines, or other sedatives. Even a single accidental dose can be fatal to a child or another person it was not prescribed for. Extended use in pregnancy can also cause a withdrawal syndrome in the newborn. (1)

Can I crush or chew a hydromorphone extended-release tablet?

No. Extended-release and controlled-release hydromorphone tablets or capsules must be swallowed whole. Breaking, chewing, dissolving, or crushing them releases a large amount of hydromorphone very quickly, which can be fatal -- especially in someone who is not already tolerant to opioids, since these formulations are for opioid-tolerant patients only. (3)

Does hydromorphone interact with other medicines the way some other opioids do (e.g. via CYP3A4)?

Not in the same way. Unlike some other opioids, hydromorphone is not significantly metabolised via the cytochrome P450 (CYP3A4) enzyme system, per the UK SmPC reviewed, so it is not expected to have the same CYP3A4-mediated interactions as opioids like buprenorphine or oxycodone. It still has serious, real interactions with benzodiazepines, alcohol, other CNS depressants, MAOIs, and serotonergic medicines. (4)

What is the mechanism of action of hydromorphone hydrochloride?

Hydromorphone is a semi-synthetic opioid, a hydrogenated ketone of morphine, acting primarily as a full agonist at the mu-opioid receptor. Unlike some other opioids, hydromorphone is not significantly metabolised via cytochrome P450 enzymes (including CYP3A4) and is not expected to inhibit CYP450 substrates, per the UK SmPC reviewed -- a genuine pharmacological difference from opioids such as oxycodone or buprenorphine that are CYP3A4 substrates. (4) (1)

What is the generic name of Hydromorphone?

The generic name is hydromorphone hydrochloride. (1) (3)

What class of drug is hydromorphone hydrochloride?

Hydromorphone is classed as: Opioid (mu-receptor) agonist -- a semi-synthetic hydrogenated ketone derivative of morphine. (1) (3)

References

  1. DILAUDID (hydromorphone hydrochloride) oral solution and tablets -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information · United States · dated 2026-01-01 · accessed 2026-07-30 · source 1
  2. DILAUDID (hydromorphone hydrochloride) injection, solution -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information · United States · dated 2026-01-01 · accessed 2026-07-30 · source 2
  3. HYDROMORPHONE HYDROCHLORIDE extended-release tablets (Padagis US LLC) -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information · United States · dated 2026-01-01 · accessed 2026-07-30 · source 3
  4. Palladone SR 2 mg hard capsules (hydromorphone hydrochloride) -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- Summary of Product Characteristics (SmPC) · United Kingdom · dated 2025-01-01 · accessed 2026-07-30 · source 4
  5. Hydromorphone -- list of nationally authorised medicinal products (PSUSA/00001686); Jurnista prolonged-release tablets EU Mutual Recognition Procedure historyEuropean Medicines Agency (EMA) -- nationally-authorised-medicinal-products list; historical mutual-recognition-procedure record · European Union · dated 2024-11-01 · accessed 2026-07-30 · source 5
  6. HYDROMORPH CONTIN (hydromorphone hydrochloride controlled-release capsules) -- Product MonographHealth Canada -- Product Monograph · Canada · dated 2023-08-25 · accessed 2026-07-30 · source 6
  7. DILAUDID hydromorphone hydrochloride tablets and injection -- ARTG entries; JURNISTA prolonged-release tablets -- discontinuation and ARTG cancellationTherapeutic Goods Administration (TGA), Australia -- Australian Register of Therapeutic Goods (ARTG); cancellations-by-sponsors register · Australia · dated 2024-01-01 · accessed 2026-07-30 · source 7
  8. Prescriber Update Vol 43(3), September 2022 -- 'Opioids and serotonergic medicines: some combinations may increase the risk of serotonin syndrome'Medsafe (New Zealand Medicines and Medical Devices Safety Authority) -- Prescriber Update · New Zealand · dated 2022-09-01 · accessed 2026-07-30 · source 8

Brand names by country

Single-ingredient hydromorphone hydrochloride names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • Dilaudid.2 mg/mL, 8 mg, 5 mg/5mL, 2 mg/mL, 4 mg, 1 mg/mL, 2 mg · fresenius kabi usa, llc

United Kingdom

  • Palladone (immediate-release capsules) (4)emc current smpc confirmed · 1.3 mg, 2.6 mg · Napp Pharmaceuticals
  • Palladone SR (sustained-release capsules) (4)emc current smpc confirmed · 2 mg, 4 mg, 8 mg, 16 mg, 24 mg · Napp Pharmaceuticals
  • Palladone (injection) (4)emc current smpc confirmed · 2 mg/mL, 10 mg/mL, 20 mg/mL, 50 mg/mL · Napp Pharmaceuticals

Canada

  • HYDROMORPH CONTIN
  • DILAUDID
  • HYDROMORPHONE HP
  • JURNISTA
  • DILAUDID HP
  • HYDROMORPHONE HYDROCHLORIDE INJECTION USP HP
  • HYDROMORPHONE HYDROCHLORIDE INJECTION HP
  • PMS HYDROMORPHONE SUPPOSITOIRE
  • PMS HYDROMORPHONE SIROP

Australia

  • Dilaudid (immediate-release tablets) (7)tga artg registered confirmed · 2 mg, 4 mg · Mundipharma Pty Ltd
  • Dilaudid / Dilaudid-HP (injection) (7)tga artg registered confirmed · 2 mg/mL standard, 10 mg/mL HP (opioid-tolerant patients only) · Mundipharma Pty Ltd
  • Jurnista (prolonged-release tablets) -- DISCONTINUED, not currently available (7)tga artg registration cancelled 2024 · 4 mg, 8 mg, 32 mg, 64 mg · Janssen-Cilag Pty Ltd
View brands in additional countries.

European Union

Jurnista (prolonged-release tablets, OROS delivery) (5), Various nationally authorised hydromorphone immediate-release and injectable products (5)

This page provides general reference information about hydromorphone and is not a substitute for advice from the prescriber managing your care. All dosing and treatment decisions, including starting, changing, or stopping this medicine, should be made with your prescriber.

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