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Opioid Analgesic (Moderate-Strong) Pregnancy: SPC §4.6, verbatim: 'Oxycodone solution is not recommended for use during pregnancy nor during labour. There are limited data from the use of oxycodone in pregnant women. Regular use in pregnancy may cause drug dependence in the foetus, leading to withdrawal symptoms in the neonate. If opioid use is required for a prolonged period in pregnant women, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. Administration during labour may depress respiration in the neonate and an antidote for the child should be readily available.' Breastfeeding: 'Administration to nursing women is not recommended as oxycodone may be secreted in breast milk and may cause respiratory depression in the newborn.' Fertility: 'No human data on the effect of oxycodone on fertility are available.'

Oxycodone

Brand names: OxyNorm, OxyContin (modified release)

Oxycodone is a strong opioid analgesic used for moderate-to-severe acute post-operative pain, available in oral and parenteral forms within a multimodal regimen.

Adult dose

Dose: 5 mg every 4-6 hours as the usual starting dose in adults over 18 years, then titrate. UK SPC §4.2, verbatim: 'The usual starting dose for opioid naive patients or patients presenting with severe pain uncontrolled by weaker opioids is 5 mg, 4-6 hourly. The dose should then be carefully titrated, as frequently as once a day if necessary, to achieve pain relief.' US immediate-release tablet cross-check, verbatim: 'Initiate treatment with oxycodone hydrochloride in a dosing range of 5 to 15 mg every 4 to 6 hours as needed for pain and at the lowest dose necessary to achieve adequate analgesia.'
Route: Oral, immediate-release only. UK SPC §4.2: 'Oxycodone is for oral use.' The fetched UK product is an oral solution 5 mg/5 mL; the fetched US product is immediate-release tablets 5, 10, 15, 20 and 30 mg. SCOPE - this covers this page's PRIMARY route (oral immediate-release opioid analgesia) and nothing else: NEITHER fetched label doses the intravenous or any parenteral route, and neither doses a modified-release oral preparation, so the IV, PCA and modified-release (OxyContin) regimens also shown on this page are NOT sourced here. The SPC gives only a conversion ratio for an already-established dose: '2 mg of oral oxycodone is equivalent to 1 mg of parenteral oxycodone.'
Frequency: Every 4-6 hours - 'Oxycodone solution should be taken at 4-6 hourly intervals' (UK SPC §4.2). Adults over 18 years. Elderly: 'A dose adjustment is not usually necessary in elderly patients... adult doses and dosage intervals are appropriate.'
Max: No maximum dose is stated in either fetched label. The SPC bounds the regimen by response rather than by a ceiling: 'Patients should be titrated to pain relief unless unmanageable adverse drug reactions prevent this' and 'Generally, the lowest effective dose for analgesia should be selected.' The US label likewise gives only 'Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals.'
INDICATION SCOPE: the SPC doses pain by severity, not by a named surgical indication, so the figures above are applied to this page's primary use - oral opioid analgesia - and to no parenteral regimen. The US label does address the surgical setting in general terms: 'Many acute pain conditions (e.g., the pain that occurs with a number of surgical procedures or acute musculoskeletal injuries) require no more than a few days of an opioid analgesic.' || PERI-OPERATIVE CAUTIONS, SPC §4.4 verbatim: 'Oxycodone solution should be used with caution pre-operatively and within the first 12-24 hours post-operatively'; 'As with all opioid preparations, oxycodone products should be used with caution following abdominal surgery as opioids are known to impair intestinal motility and should not be used until the physician is assured of normal bowel function'; 'Patients about to undergo additional pain relieving procedures (e.g. surgery, plexus blockade) should not receive Oxycodone solution for 6 hours prior to the intervention.' || CONVERSION FROM ORAL MORPHINE, SPC §4.2: 'Patients receiving oral morphine before oxycodone therapy should have their daily dose based on the following ratio: 10 mg of oral oxycodone is equivalent to 20 mg of oral morphine' - a guide only, with each patient titrated individually. The SPC ratio is 2:1 oral morphine to oral oxycodone. || TREATMENT GOALS: 'Prior to starting treatment with opioids, a discussion should be held with patients to put in place a strategy for ending treatment with oxycodone in order to minimise the risk of addiction and drug withdrawal syndrome'; 'Oxycodone should not be used for longer than necessary'; on stopping, 'it may be advisable to taper the dose gradually to prevent symptoms of withdrawal'. || NON-MALIGNANT PAIN: 'Opioids are not first line therapy for chronic non-malignant pain, nor are they recommended as the only treatment.' || PAEDIATRICS: paedDose is null because SPC §4.2 states 'Oxycodone solution should not be used in patients under 18 years.' No paediatric section was fetched from the US label.

Dose adjustments

Renal

Halve the starting dose and titrate. SPC §4.2, 'Patients with renal or hepatic impairment', verbatim: 'The plasma concentration in this patient population may be increased. The dose initiation should follow a conservative approach in these patients. The recommended adult starting dose should be reduced by 50% (for example a total daily dose of 10 mg orally in opioid naive patients), and each patient should be titrated to adequate pain control according to their clinical situation.' §4.4 additionally lists 'patients with impaired hepatic or renal function' among those in whom caution must be exercised. No creatinine-clearance thresholds are given in the fetched text.

Hepatic

Same 50% starting-dose reduction as for renal impairment (SPC §4.2, quoted under renalAdjustment). Note that §4.3 makes 'moderate to severe hepatic impairment' an outright CONTRAINDICATION, so the 50% reduction applies only to mild impairment.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to oxycodone or to any of the excipients listed in section 6.1 (SPC §4.3)
  • Severe respiratory depression with hypoxia (SPC §4.3)
  • Paralytic ileus (SPC §4.3)
  • Acute abdomen (SPC §4.3)
  • Delayed gastric emptying (SPC §4.3)
  • Severe chronic obstructive lung disease (SPC §4.3)
  • Cor pulmonale (SPC §4.3)
  • Severe bronchial asthma (SPC §4.3)
  • Elevated carbon dioxide levels in the blood (SPC §4.3)
  • Moderate to severe hepatic impairment (SPC §4.3)
  • Chronic constipation (SPC §4.3)
  • Caution, not contraindication, but §4.4 requires it in: the debilitated elderly; opioid-dependent patients; severely impaired pulmonary function; impaired hepatic or renal function; myxoedema, hypothyroidism, Addison's disease, toxic psychosis, prostate hypertrophy, adrenocortical insufficiency, alcoholism, delirium tremens, biliary tract disease, pancreatitis, inflammatory bowel disorders, hypotension, hypovolaemia, raised intracranial pressure, intracranial lesions or head injury, reduced level of consciousness of uncertain origin, sleep apnoea, and patients taking benzodiazepines, other CNS depressants (including alcohol) or MAO inhibitors

Side effects

  • Very common (>= 1/10): somnolence, dizziness, headache (SPC §4.8)
  • Very common: constipation, nausea, vomiting
  • Very common: pruritus
  • Common (>= 1/100 to 1/10): anxiety, confusional state, depression, insomnia, nervousness, abnormal thinking, abnormal dreams
  • Common: tremor, lethargy, sedation
  • Common: dyspnoea, bronchospasm, cough decreased
  • Common: abdominal pain, diarrhoea, dry mouth, dyspepsia; decreased appetite
  • Common: rash, hyperhidrosis; asthenia, fatigue
  • Uncommon: respiratory depression, hiccups - 'The primary risk of opioid excess is respiratory depression' (§4.4)
  • Uncommon: urinary retention, ureteral spasm; erectile dysfunction, hypogonadism
  • Uncommon: amnesia, convulsion, hypertonia, hypoaesthesia, involuntary muscle contractions, speech disorder, syncope, paraesthesia, dysgeusia, hypotonia
  • Uncommon: visual impairment, miosis; vertigo; palpitations (in the context of withdrawal syndrome), supraventricular tachycardia; vasodilatation, facial flushing
  • Uncommon: hypersensitivity; frequency not known: anaphylactic reaction, anaphylactoid reaction
  • Uncommon: increased hepatic enzymes, biliary colic; dysphagia, flatulence, eructation, ileus, gastritis
  • Rare: hypotension, orthostatic hypotension; urticaria
  • Frequency not known: hyperalgesia; drug dependence; opioid tolerance; opioid withdrawal syndrome; neonatal drug withdrawal syndrome
  • Frequency not known: central sleep apnoea syndrome - 'Opioid use increases the risk of CSA in a dose-dependent fashion' (§4.4)

Monitoring

  • Respiratory rate and level of sedation - 'The patient should be followed closely for signs and symptoms of respiratory depression and sedation', particularly where a sedative medicine such as a benzodiazepine is co-prescribed (SPC §4.4)
  • Sleep-related breathing: 'In patients who present with CSA, consider decreasing the total opioid dosage' (§4.4)
  • Bowel function - discontinue immediately if paralytic ileus is suspected or occurs, and after abdominal surgery do not use 'until the physician is assured of normal bowel function' (§4.4)
  • Ongoing need for treatment - 'During treatment, there should be frequent contact between the physician and the patient to evaluate the need for continued treatment, consider discontinuation and to adjust dosages if needed' (§4.2)
  • If pain control is inadequate, 'the possibility of hyperalgesia, tolerance and progression of underlying disease should be considered' (§4.2)
  • Signs of addiction, abuse and misuse, with an agreed exit strategy set before initiation (§4.2/§4.4)
  • On stopping, taper gradually and watch for withdrawal (§4.2)
  • Neonate of a mother treated in pregnancy - 'an antidote for the child should be readily available' when given during labour (§4.6)

Clinical monograph

How it works

Oxycodone is a potent agonist principally at mu-opioid receptors, inhibiting ascending pain pathways and modifying the perception of pain.

Prescribing in practice

  • As with all strong opioids the key hazard is dose-related respiratory depression and sedation — titrate to effect, avoid concurrent sedatives where possible, and ensure naloxone and monitoring are available.
  • Oxycodone is metabolised hepatically and partly renally excreted, so reduce dosing and extend intervals in hepatic or renal impairment and in the elderly.
  • Anticipate and manage opioid constipation, nausea and the risk of dependence; switch to non-opioid analgesia as pain improves.

Monitoring

Monitor pain score, sedation level, respiratory rate and bowel function, with closer observation after dose changes or in organ impairment.

Counselling the patient

  • This is a strong painkiller for after your operation — take it as prescribed and step down as pain eases.
  • It can cause drowsiness and constipation; do not drive while affected.
  • Report excessive sleepiness or slow breathing immediately.

Evidence & guidelines

Oxycodone is an established strong opioid for acute post-operative pain within multimodal analgesia.

Reference: OxyNorm SPC; FACULTY of Pain Medicine Opioid Prescribing Guidelines; PROSPECT Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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