Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Dual-Mechanism Opioid Analgesic (MOR + NRI) Pregnancy: Very limited data in pregnant women — should be used during pregnancy only if the potential benefit justifies the potential risk to the foetus. Long-term maternal opioid use co-exposes the foetus and the newborn may experience neonatal opioid withdrawal syndrome, which can be life-threatening if not recognised and treated; an antidote for the newborn should be readily available. Not recommended during and immediately before labour and delivery, and newborns of mothers taking tapentadol should be monitored for respiratory depression. Should not be used during breast-feeding.

Tapentadol

Brand names: Palexia, Palexia SR

Tapentadol is a centrally acting opioid analgesic used for moderate to severe acute and chronic pain, including musculoskeletal and post-operative pain.

Adult dose

Dose: 50 mg tapentadol as a prolonged-release tablet twice daily (starting dose in patients not currently taking opioid analgesics)
Route: Oral — prolonged-release tablets must be taken whole with sufficient liquid, not divided or chewed, to maintain the prolonged-release mechanism; may be taken with or without food
Frequency: Twice daily, approximately every 12 hours
Max: Total daily doses greater than 500 mg tapentadol have not yet been studied and are therefore not recommended
PROVENANCE/FORMULATION: the fetched SPC is a PROLONGED-RELEASE (twice-daily) tapentadol product — it does not cover immediate-release tapentadol, and no immediate-release regimen is given here; consult the relevant SPC if an immediate-release product is intended. TITRATION: after initiation the dose should be titrated individually under close supervision to a level giving adequate analgesia with minimal undesirable effects; clinical trial experience showed increments of 50 mg twice daily every 3 days were appropriate in most patients. Patients switching from other opioids may need higher initial doses, taking into account the nature of the previous medicinal product, its administration and the mean daily dose. Agree treatment duration, goals and an end-of-treatment plan with the patient before starting; maintain frequent contact to review the need for continued treatment; taper gradually when stopping to prevent withdrawal; consider hyperalgesia, tolerance and progression of the underlying disease if pain control is inadequate. HEPATIC IMPAIRMENT: mild — no adjustment; moderate — use with caution, initiate at the lowest available strength (50 mg prolonged-release) no more frequently than once every 24 hours and do not exceed 50 mg daily at initiation; severe — not studied, use not recommended. Elderly (65 years and over): generally no dose adaptation required, but take care because of the greater likelihood of decreased renal and hepatic function. Some sections of the product information we used were incomplete — check the full SPC.

Paediatric dose

Dose: 1.5 mg/kg
Route: oral
Frequency: every 12 hours
Max: Starting dose must not exceed 50 mg; maximum recommended dose 3.5 mg per kg body weight every 12 hours; a total dose of 500 mg per day (250 mg every 12 hours) should not be exceeded
Prolonged-release tablets. Children and adolescents from 6 years to less than 18 years not currently taking opioid analgesics: recommended starting dose 1.5 mg per kg body weight every 12 hours, with 25 mg or 50 mg tablet strengths considered as starting doses. Titrate individually with increments of 25 mg for patients under 40 kg, or 25 mg or 50 mg for patients over 40 kg, after a minimum of 2 days since the last increase, within the general recommended range of 1.5 mg/kg to 3.5 mg/kg; individual patients have shown benefit from doses down to 1.0 mg/kg. Patients already taking opioids may require higher initial doses. Safety and efficacy below 6 years of age have not been established (not recommended); not studied and not recommended in children and adolescents with renal or hepatic impairment. Verify against a children's formulary before prescribing.

Dose adjustments

Renal

Mild or moderate renal impairment: no dosage adjustment required. Severe renal impairment: not studied in controlled efficacy trials — use in this population is not recommended.

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.

Paediatric weight-based calculator

Prolonged-release tablets. Children and adolescents from 6 years to less than 18 years not currently taking opioid analgesics: recommended starting dose 1.5 mg per kg body weight every 12 hours, with 25 mg or 50 mg tablet strengths considered as starting doses. Titrate individually with increments of 25 mg for patients under 40 kg, or 25 mg or 50 mg for patients over 40 kg, after a minimum of 2 days since the last increase, within the general recommended range of 1.5 mg/kg to 3.5 mg/kg; individual patients have shown benefit from doses down to 1.0 mg/kg. Patients already taking opioids may require higher initial doses. Safety and efficacy below 6 years of age have not been established (not recommended); not studied and not recommended in children and adolescents with renal or hepatic impairment. Verify against a children's formulary before prescribing.

Verify in a children's formulary

Contraindications

  • Hypersensitivity to tapentadol or to any of the excipients
  • Situations where active substances with mu-opioid receptor agonist activity are contraindicated, i.e. significant respiratory depression (in unmonitored settings or the absence of resuscitative equipment) and acute or severe bronchial asthma or hypercapnia
  • Any patient who has or is suspected of having paralytic ileus
  • Acute intoxication with alcohol, hypnotics, centrally acting analgesics or psychotropic active substances

Side effects

  • Nausea and constipation (very common); vomiting, diarrhoea and dyspepsia (common)
  • Dizziness, somnolence and headache (very common)
  • Anxiety, depressed mood, sleep disorder, nervousness, restlessness (common); confusional state, disorientation, hallucinations (uncommon); delirium (post-marketing)
  • Respiratory depression (rare) and dyspnoea (uncommon) — dose-related at high doses or in mu-opioid-sensitive patients
  • Drug dependence, opioid use disorder and drug withdrawal syndrome; asthenia, fatigue, hyperhidrosis, pruritus and rash
  • Blood pressure decreased, heart rate increased or decreased, palpitations; convulsion (rare); drug hypersensitivity with post-marketing angioedema, anaphylaxis and anaphylactic shock

Interactions

  • Sedating medicinal products such as benzodiazepines or related substances — concomitant use may result in sedation, respiratory depression, coma and death; reserve for patients with no alternative, consider reducing the dose of one or both agents, keep the duration as short as possible and monitor closely (§4.4)
  • Alcohol, hypnotics, centrally acting analgesics and psychotropic active substances — contraindicated in acute intoxication with these substances (§4.3)
  • Concomitant opioids and psychoactive drugs should be reviewed because of the risk of opioid use disorder and overdose (§4.4)
  • This interaction list may be incomplete — check the full SPC.

Clinical monograph

How it works

It combines mu-opioid receptor agonism with noradrenaline reuptake inhibition, providing analgesia through two complementary mechanisms.

Prescribing in practice

  • As an opioid it can cause respiratory depression, dependence and overdose, with risk increased by concomitant benzodiazepines, alcohol or other CNS depressants.
  • Because of its noradrenergic action it should be used with caution with serotonergic and other monoaminergic drugs owing to the risk of serotonin syndrome, and it is contraindicated with or close to monoamine oxidase inhibitors.
  • It can lower the seizure threshold and should be used cautiously in patients with epilepsy or a history of seizures.

Monitoring

Monitor pain relief, sedation, respiratory status and for signs of tolerance or dependence during treatment.

Counselling the patient

  • Do not drink alcohol while taking this medicine, and tell your team about any sedatives you use.
  • It may cause drowsiness and affect your ability to drive or operate machinery.
  • Do not stop suddenly after prolonged use; the dose should be reduced gradually.

Evidence & guidelines

Tapentadol is an established option for moderate to severe pain in current prescribing references.

Reference: MHRA Drug Safety Update 2013; SPC Palexia SR; CONIFER trial; NICE CG173; NICE NG59; 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.

Calculators
Pathways