Hydromorphone

Emergency & Prehospital

• Severe acute pain needing an opioid: fractures, burns, major trauma or renal colic. Use it when non-opioid analgesia is inadequate. The FDA label puts it this way: pain severe enough to need an opioid when alternatives are inadequate.
• Palliative or hospice pain crisis: subcutaneous breakthrough dosing for palliative patients only (doses in the Dosing tables)

ED / ICU / Transport

• Severe acute pain in the ED: abdominal, musculoskeletal or renal colic pain, as part of multimodal analgesia with acetaminophen or ketorolac where appropriate
• Sickle cell vaso-occlusive pain: use the acute pain dosing above. This page does not give pathway-specific pediatric dosing.
• Postoperative pain: intermittent IV dosing or IV patient-controlled analgesia (PCA)
• ICU analgesia: intermittent bolus or infusion as the opioid component of analgesia-first sedation in ventilated adults
• Interfacility transport: patients arriving on a hydromorphone infusion or PCA

Other Uses

• Cancer pain and severe chronic pain: oral immediate-release, extended-release (opioid-tolerant only) or continuous subcutaneous infusion
• Opioid-tolerant patients needing high doses: high-potency formulation (HPF) injection only

Doses below are typical. Confirm them against your agency protocol and the patient's opioid tolerance.

Available Forms

• Injection, standard: 1 mg/mL, 2 mg/mL and 4 mg/mL single-dose vials; 2 mg/mL multiple-dose vial (40 mg in 20 mL); prefilled syringes 0.2 mg/mL, 0.5 mg/0.5 mL, 1 mg/mL and 2 mg/mL (Dilaudid). EMS and transport stock is agency-specific.
• Injection, high-potency formulation (HPF): 10 mg/mL in 1 mL, 5 mL and 50 mL vials; opioid-tolerant patients only
• Oral immediate-release: 2 mg, 4 mg and 8 mg tablets; oral solution 1 mg/mL (5 mg/5 mL)
• Oral extended-release: 8 mg, 12 mg, 16 mg and 32 mg tablets, once daily, opioid-tolerant patients only. Swallow whole: never cut, crush, chew or dissolve them. Never crush one for a feeding tube. Doing so releases a potentially fatal dose.
• Rectal: 3 mg suppository

Adult Dosing

Pediatric Dosing

Pediatric doses come from three sources, in this order. First, the 2025 AHA Guidelines for CPR and ECC, where they state a dose. Then the NASEMSO National Model EMS Clinical Guidelines v3.0 (2022). Then the US label. Where none of them gives a dose, none is shown. A pediatric maximum never exceeds the adult maximum dose (NASEMSO Universal Care Guideline). Doses are off-label unless marked labeled. NASEMSO generally defines pediatric patients as up to 40 kg or up to 14 years of age, whichever comes first.

Double-check the weight-based math with weight-based dosing or the Broselow tape.

Preparation & Administration

• Push rate: Go slowly, over at least 2–3 min. A rapid IV push increases hypotension and respiratory depression.
• Prefilled syringes: Do not dilute for IV push. Do not add other fluids to the syringe (label). Single dose only. Discard the remainder as controlled-substance waste.
• Admixtures: Physically compatible and chemically stable for at least 24 hr at 25 °C (77 °F), protected from light, in most common large-volume solutions. A 0.2 mg/mL admixture in 0.9% sodium chloride or 5% dextrose is labeled.
• Inspect: A slight yellow tint may develop with no loss of potency. Discard if particulate is present.
• Pump requirement: PCA and continuous infusions run on a smart pump. Select the drug library entry and the correct concentration.
• PCA settings: Check the demand dose, lockout, hourly limit and any basal rate at every handoff.
• PCA: Only for patients who can press the button themselves. No PCA by proxy. UCSF lists the inability to push the button independently as a contraindication. Only the patient presses the dose button. ASRA: the patient controls the activation button.

Contraindications

• Significant respiratory depression
• Acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment
• Known or suspected gastrointestinal obstruction, including paralytic ileus
• Hypersensitivity to hydromorphone, its salts, any product component, or sulfite-containing medications (many products contain sodium metabisulfite)
• HPF (10 mg/mL) injection and extended-release tablets: patients who are not opioid-tolerant
• Extended-release tablets: GI tract narrowed by surgery or disease, "blind loops" of the GI tract, or GI obstruction

Precautions

• Older, cachectic or debilitated patients; COPD, cor pulmonale, low respiratory reserve: Apnea can occur at recommended doses. Start low and monitor closely.
• Sleep-disordered breathing: Opioids cause central sleep apnea and sleep-related hypoxemia. The effect is dose-dependent.
• Hypovolemia or shock: Vasodilation can cause severe hypotension. Avoid in circulatory shock.
• Head injury, raised ICP, brain tumor: CO₂ retention raises ICP. Opioids also obscure the neurologic exam. Avoid in impaired consciousness or coma.
• Seizure disorders: May increase seizure frequency.
• Biliary disease or pancreatitis: The risk is sphincter of Oddi spasm. Watch for worsening symptoms.
• Personal or family history of substance use or mental illness: A higher risk of addiction and misuse. That history does not justify withholding treatment of severe pain.

Hold / Reassess If

• Hard to rouse, or falls asleep mid-conversation: hold the next dose, stimulate, check breathing
• RR <10/min, SpO₂ <90% or EtCO₂ >50 mmHg: hold, support ventilation, consider naloxone
• SBP <90 mmHg or MAP <65 mmHg: hold, treat hypovolemia, reassess

Common

• Lightheadedness, dizziness, sedation
• Nausea and vomiting
• Sweating, flushing and pruritus
• Dysphoria or euphoria
• Dry mouth
• Constipation and urinary retention with repeated doses
• Long-term use: opioid-induced esophageal dysfunction (dysphagia, regurgitation, non-cardiac chest pain), more likely at higher doses and longer durations

You will not find reliable frequencies on this label. Effects show up more in ambulatory patients, and in patients who are not in severe pain.

Serious / Life-Threatening

Overdose & Toxicity Management

• Signs: respiratory depression, somnolence to coma, flaccidity, cold clammy skin, miosis (mydriasis with severe hypoxia); possible pulmonary edema, bradycardia, hypotension, hypoglycemia and airway obstruction.
• Immediate management: Open and protect the airway and ventilate first. Give oxygen, and vasopressors for shock. Cardiac arrest: CPR and ACLS/PALS take priority (2025 AHA Guidelines for CPR and ECC, Part 10, opioid overdose recommendations 1 and 3 (COR 1, B-NR): breaths or bag-mask first, then an opioid antagonist for respiratory arrest with a pulse. Recommendations 5 and 6 (COR 2b, B-NR and C-EO): an antagonist may be reasonable in cardiac arrest if CPR is not interrupted).
• Antidote: naloxone. Adult overdose (label): 0.4–2 mg IV, repeated every 2–3 min as needed and titrated to breathing. IM or SC if there is no IV access. No response after 10 mg total? Question the diagnosis. Pediatric overdose (label): 0.01 mg/kg IV. No response? Give 0.1 mg/kg. With no IV access, give IM or SC in divided doses. Pediatric postoperative (iatrogenic) depression (label): 0.005–0.01 mg IV increments (an absolute dose, not per kg) every 2–3 min to the desired reversal. Hydromorphone labeling also names nalmefene as a reversal agent.
• Re-sedation: Naloxone wears off before hydromorphone does. Monitor until spontaneous breathing is reliably maintained, and repeat naloxone if needed. In physically dependent patients, titrate smaller doses to avoid acute withdrawal.
• Going home on oral hydromorphone: Discuss it and provide access to naloxone or nalmefene. That matters most with CNS depressants, a history of overdose or children in the home.
• Late complication: Toxic leukoencephalopathy can show up hours to weeks after apparent recovery.

Clinically Significant Interactions

Hydromorphone clears by glucuronidation, not CYP450. That is why it lacks the CYP3A4 interactions of fentanyl and oxycodone.

IV Compatibility

• Diluents: NS or D5W. Stable for at least 24 hr at 25 °C (77 °F), protected from light, in most common large-volume solutions.
• Prefilled syringes: Give undiluted. Do not add other fluids.
• Y-site: Flush before and after other drugs when a line is shared.
• Verify with an institutional compatibility resource.

• Pediatrics: FDA labeling says safety and effectiveness are not established. Weight-based use is off-label and protocol-driven. Doses are in the Pediatric Dosing table. Even one accidental oral dose in a child is potentially fatal. Treat it that way.
• Neonates: No standard dose on this page. Specialist dosing only. Newborns of mothers on prolonged opioids need observation for neonatal opioid withdrawal syndrome. The label requires an opioid reversal agent (naloxone or nalmefene) to be available at delivery after maternal opioid use. A newborn with poor breathing needs effective ventilation first, per NRP. Naloxone is not routine in neonatal resuscitation. In newborns of mothers with long-term opioid use or dependence, it can precipitate withdrawal, including seizures.
• Pregnancy: There are no human data on major birth defects or miscarriage. Some animal studies showed harm at high doses. Prolonged use can cause neonatal opioid withdrawal syndrome. Not recommended during or just before labor when other analgesia is appropriate. Opioids cross the placenta and can depress the newborn's breathing. Short-term use for severe pain is not contraindicated. Use the lowest effective dose.
• Lactation: Low levels enter breast milk. Monitor the infant for excess sedation and breathing problems. Also watch for withdrawal when maternal dosing or breastfeeding stops. Extended-release tablets: breastfeeding not recommended (ER label).
• Older Adults: More sensitive to sedation and respiratory depression. The label says to reduce the initial dose in the elderly or debilitated, and to start at 0.2 mg IV, then titrate slowly. The label reserves concomitant use with benzodiazepines, gabapentinoids and other CNS depressants for patients with no adequate alternative.
• Renal Impairment: Start at one-fourth to one-half the usual dose. Exposure is about 2-fold at CrCl 40–60 mL/min and 4-fold at CrCl <30 mL/min (single 4 mg oral dose), and the half-life gets longer. The metabolite H3G accumulates and can cause neuroexcitation. In severe CKD or dialysis, use the low end of the range and titrate slowly. Extended-release tablets: start at 50% of the usual dose in moderate and 25% in severe renal impairment (ER label).
• Hepatic Impairment: Moderate impairment (Child-Pugh B) raises exposure about 4-fold. Start at one-fourth to one-half the usual dose. Severe impairment has not been studied, and the label expects a further increase in exposure. Extended-release tablets: alternate analgesics are recommended in severe hepatic impairment (ER label).
• Obesity / Dosing Weight: The label's IV and IM doses are fixed. The NASEMSO prehospital dose is weight-based (0.015 mg/kg, max initial 2 mg, cumulative 4 mg). Use actual weight and stay under the caps. Obesity and sleep apnea raise the risk of respiratory depression. Start low and use EtCO₂. Pediatric doses never exceed the adult maximum (NASEMSO Universal Care Guideline).
• Opioid-Tolerant Patients: Usual doses may be inadequate. Only these patients may receive HPF or extended-release products. Do not stop or rapidly reduce therapy in physically dependent patients. Rapid reduction has caused serious withdrawal, uncontrolled pain and suicide. Long-term oral therapy: start the taper with a cut of no more than 10% to 25% of the total daily dose. Then lower the dose every 2 to 4 weeks (oral label). Pause or slow the taper if withdrawal appears. Short inpatient injection courses can be tapered faster (injection label: 25–50% every 2–4 days).

• Scope: Paramedic, critical-care transport and RN per protocol. Many EMS systems carry fentanyl or morphine instead, and some limit hydromorphone to palliative care. Scope varies by state and agency protocol.
• Storage & Stability: Store at 20–25 °C (68–77 °F). Excursions to 15–30 °C (59–86 °F) are allowed. Protect from light. Schedule II means secure storage, counts and witnessed waste.
• Carried Concentration: Confirm the concentration at the cross-check. Vials are 1, 2 or 4 mg/mL. Prefilled syringes run as dilute as 0.2 mg/mL or 0.5 mg/0.5 mL, so 1 mL is not always 1 mg. State the dose in mg and mL. If a sending facility has an HPF (10 mg/mL) infusion running, confirm opioid tolerance and the pump concentration before departure.
• Infusions in Transport: Use a smart pump with the drug library, on a dedicated or clearly labeled line. Verify concentration, rate, PCA dose, lockout and last bolus at handoff. Carry enough volume for the trip plus delays. Monitor SpO₂ and EtCO₂ continuously.
• Handoff Essentials: time, dose in mg and route of each dose, total given, sedation level, RR and EtCO₂ trend, any naloxone given, and current infusion or PCA settings.

Mechanism of Action

• Full μ-opioid receptor agonist (relatively selective, and it binds other opioid receptors at higher doses). Analgesia has no ceiling effect. The dose is limited by sedation and respiratory depression.
• Brainstem respiratory centers respond less to CO₂. The result is hypoventilation and apnea, and miosis even in darkness.
• GI smooth muscle is slowed. Motility drops and the sphincter of Oddi spasms. The result is constipation, ileus and biliary pain.
• Peripheral vasodilation and histamine release cause orthostatic hypotension, flushing and pruritus.
• More lipophilic than morphine, so it reaches the CNS faster.

Pharmacokinetics

• Half-life: About 2.3 hr after IV and 2.6–2.8 hr after oral doses. It is prolonged in severe renal impairment.
• Metabolism: Hepatic glucuronidation. More than 95% becomes hydromorphone-3-glucuronide (H3G), with minor 6-hydroxy metabolites. There is no CYP450 pathway.
• Active metabolites: H3G has no analgesic activity. When it accumulates, though, it is neuroexcitatory.
• Elimination: Renal, mainly as H3G. Little comes out as unchanged drug.
• Bioavailability / distribution: oral about 24% (first-pass); protein binding 8–19%; Vd about 300 L.

Generic Name

Hydromorphone hydrochloride

Brand Names

Dilaudid (injection, tablets, oral solution); generic injection (standard and HPF), tablets, oral solution, extended-release tablets and suppositories

Pharmacologic Class

Semi-synthetic full μ-opioid receptor agonist (hydrogenated ketone of morphine)

Therapeutic Class

Opioid analgesic

Controlled Substance

C-II (DEA Schedule II)

ISMP High-Alert

Yes: ISMP high-alert medication (opioids, IV and oral)

Look-Alike / Sound-Alike

HYDROmorphone / morphine; standard 1–4 mg/mL vs HPF 10 mg/mL vials

Error-Prone Abbreviations to Avoid

Do not abbreviate drug names (e.g., MS or MSO4 for morphine); write mg and mL in full for oral solution