Hydromorphone
DILAUDID
Pronunciation: hye-droe-MOR-foen
“Dial, you did (to say) Hi (on) more phones”
pinpoint pupils → opioid
Several opioids are metabolized to hydromorphone, “All lines lead to hydro–”more phones”
What it isPotent full mu-opioid agonist; severe pain.
Why this oneHas no analgesically active metabolite and releases less histamine than morphine, useful when morphine is poorly tolerated.
What limits itConversion errors can be fatal because of its potency; its glucuronide still accumulates in renal failure and can cause myoclonus.
Pearls
- Reduce starting dose in moderate-to-severe renal impairment.
Hydromorphone prescription history
Animated chart of estimated U.S. prescriptions per year, Opioid analgesics (1900–2026). Hydromorphone enters in 1926 (estimated).
FDA-approved for
- pain (~1984)
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityRespiratory depression, dependence and overdose; risk rises sharply with sedatives or impaired clearance.
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Pain (severe, requiring opioid) | opioid-naive adult | 2-4 mg PO q4-6h PRN |
Renal Start at 1/4 to 1/2 usual starting dose per degree of impairment
Hepatic Start at 1/4 to 1/2 usual starting dose per degree of impairment; severe impairment not studied
When converting from another opioid, start at ~half the usual dose
Instructions
- Use lowest effective dose for shortest duration
- Supplemental dose 5-15% of total daily dose q2h PRN
- Do not stop abruptly in physically dependent patients; taper ~10-25% every 2-4 weeks
- Ensure access to an opioid overdose reversal agent (naloxone/nalmefene)
Available strengths
- tab 2, 4, 8 mg
- ER tab 8, 12, 16, 24, 32 mg
- sol 40 mg/20 mL
- sol 5 mg/5 mL
- supp 3 mg
- inj 0.2, 1, 2, 4, 10 mg/mL
Contraindications
- Significant respiratory depression
- Acute or severe bronchial asthma (unmonitored / no resuscitative equipment)
- Known or suspected GI obstruction, including paralytic ileus
- Known sulfite hypersensitivity
Cautions
- Opioid-induced hyperalgesia/allodynia
- Respiratory depression in COPD, elderly, cachectic, or debilitated patients
- Adrenal insufficiency
- Severe hypotension; avoid in circulatory shock
- Avoid with increased ICP, brain tumor, head injury, or impaired consciousness
- Serotonin syndrome with serotonergic drugs
- Seizures
Adverse reactions
- Lightheadedness, dizziness, sedation
- Nausea, vomiting
- Sweating, flushing
- Dysphoria/euphoria, dry mouth
- Pruritus
- Constipation
Pregnancy No human data; prolonged use may cause neonatal opioid withdrawal syndrome; not recommended during labor
Lactation Low levels in human milk; monitor infant for sedation and respiratory depression
Cost
| Strength | #/mo | generic $/unit | CostPlus | |
|---|---|---|---|---|
| 2 mg | tab | per unit | $0.17/ea | not offered |
| 4 mg | tab | per unit | $0.22/ea | not offered |
| 8 mg | tab | per unit | $0.56/ea | not offered |
Other forms: Hydromorphone ER (EXALGO)
Generic entry1995
Serotonicity
This drug is routinely called serotonergic. By Gillman’s human-effect criteria it does not raise serotonin in the synapse.
Opioid effects and respiratory/CNS-depressant interactions remain important, but this drug is not a clinically significant SRI by the Gillman framework.
Gillman’s four human testsA measurable SERT affinity that fails all four is not clinical serotonicity.
- Retarded orgasm
- Efficacy in OCD and cataplexy
- Clonus and hyperreflexia in single-drug overdose
- Serotonin toxicity when combined with an MAOI
Non-elevating actionNone recorded
Evidence confidenceHigh
Background: what serotonicity is · what is and is not an SRI · what counts as a relevant MAOI.
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Memory aids: interaction avatars
Open Hydromorphone in the interactive console ↗
Self-check
- Why can hydromorphone suit patients who tolerate morphine poorly?
Less histamine release. - What can hydromorphone glucuronide accumulation in renal failure cause?
Myoclonus.