Opioids · Pain & inflammation
Hydromorphone
Dilaudid® · Hydromorph Contin®(brand names vary by market)
Morphine's substitute when the kidneys fail, and five times as strong by mouth.
Also: modified release, oral liquid, injection, infusion
Mechanism
Mu opioid receptor agonist, more potent than morphine and without clinically significant active renally-cleared metabolites.
Indications
- Moderate to severe pain
- Cancer pain
- Pain in renal impairment
Formulations
Dosing concepts
Potency
Roughly five times morphine's potency by mouth. Confusing the two milligram for milligram is one of the most dangerous substitution errors in the formulary.
Renal impairment
Preferred over morphine because its metabolites do not accumulate to the same clinical effect.
Concepts, not prescribing instructions. Practice numbers live in current references and local protocols.
Pharmacokinetics
- Bioavailability
- ~50% oral
- Half-life
- 2 to 3 h
- Elimination
- hepatic: Glucuronidation; the main metabolite has little analgesic activity
- Protein binding
- ~20%
Adverse effects
- Constipationcommon
- Sedationcommon & serious
- Respiratory depressionserious
- Nauseacommon
- Dependence and use disorderserious
Contraindications & precautions
Contraindications
- Respiratory depression
- Paralytic ileus
Precautions
- Opioid-naive patients, given the potency
- Concurrent sedatives
- Older adults
Interactions
No curated interaction entries yet for this agent.
Monitoring
Sedation and respiratory rate
Potency makes errors less forgiving
Bowel function
Class effect from the first dose
Total daily dose across all routes and formulations
Where conversion errors surface
Counselling points
- This is a strong painkiller; the dose numbers are smaller than other opioids for the same effect.
- Take your laxative regularly.
- Do not combine with alcohol or sedatives.
- Store it securely.
Clinical pearls
- The classic serious error is substituting hydromorphone for morphine at the same number of milligrams, which delivers roughly a fivefold overdose. Every conversion should be written out and double-checked.
- It is the pragmatic choice in renal failure, and knowing that single fact resolves a great many palliative and ward prescribing questions.
References & review
- Hydromorphone product monograph (consult the current version for your market) (monograph)
- Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed. (reference-work)
Last reviewed 2026-08-16 · jurisdiction: global · drug information changes; verify against current references before practice use.