Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Mixed agonist-antagonist opioid Pregnancy: SPC section 4.6: reproduction studies in animals have shown no evidence of teratogenic effect; no experience is available in human beings. Meptazinol should not be used during pregnancy unless considered essential by the physician. Regular use during 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 a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure appropriate treatment will be available. Administration during labour may depress respiration in the neonate and an antidote for the child should be readily available. Breast-feeding: not recommended as meptazinol may be secreted in breast milk and may cause respiratory depression in the infant; should not be given to lactating women unless considered essential by the physician.

Meptazinol

Brand names: Meptid

Meptazinol is an opioid analgesic with partial agonist activity used for the short-term treatment of moderate pain, including obstetric, postoperative, and renal colic pain.

Adult dose

Dose: Adults - short term treatment of moderate pain: 200 mg (one 200 mg tablet; each Meptid tablet contains 200 mg of meptazinol as hydrochloride) 3-6 hourly as required; usually one tablet 4 hourly
Route: Oral (tablets)
Frequency: Every 3-6 hours as required; usually every 4 hours
The pinned product is MEPTID TABLETS 200MG (PL169730017, Almirall, S.A.), an oral tablet; section 4.1: 'indicated for the short term treatment of moderate pain'. NOT COVERED BY THIS PRODUCT: the intramuscular route and any obstetric (labour) analgesia dose - this tablet SPC prints neither, so no IM or obstetric dose is written; section 4.6 only says administration during labour may depress respiration in the neonate and an antidote for the child should be readily available. NOT PRINTED, so not written: any maximum daily dose (maxDose unset). Elderly: 'The adult dosage schedule can be used in the elderly.' Children: 'No data are available', so paedDose is null. Section 4.2: before starting treatment with opioids, hold a discussion with the patient to put in place a strategy for ending treatment with meptazinol, to minimise the risk of addiction and drug withdrawal syndrome. Section 4.4: safety in long term use is not known, so use for moderate pain for short periods of time; clinical need for analgesic treatment should be reviewed regularly; taper the dose gradually when the patient no longer requires therapy. The tablets contain sunset yellow FCF (E 110), which may cause allergic-type reactions including asthma.

Dose adjustments

Renal

SPC section 4.4: patients with moderate to severe renal impairment should be given a reduced dose as the effect in these patients may be prolonged and increased; cerebral sensitivity may also be increased. No reduced figure is printed.

Hepatic

SPC section 4.4: patients with hepatic impairment should be given a reduced dose as opioid analgesics may precipitate coma in these patients. No reduced figure is printed.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substance or to any of the excipients
  • Acute alcoholism and where there is a risk of paralytic ileus
  • Raised intracranial pressure or head injury
  • Acute respiratory depression
  • During an asthma attack
  • Patients on monoamine-oxidase inhibitors (MAOIs) and for 14 days after discontinuing an MAOI

Side effects

  • Dizziness, headache, vertigo, somnolence, drowsiness; abdominal pain, constipation, diarrhoea, dyspepsia, nausea, vomiting (listed in the SPC table; the frequency columns cannot be read reliably from the extracted text, so no frequency is stated)
  • Hypotension; respiratory depression; increased sweating, rash
  • Drug withdrawal syndrome and drug dependence (see section 4.4)
  • Opioid-class reactions: difficulty with micturition, ureteric or biliary spasm, dry mouth, facial flushing, bradycardia, tachycardia, palpitations, hypothermia, dysphoria, mood changes, miosis, decreased libido or potency, urticaria and pruritus
  • Very rare reports of psychiatric disorders (hallucination, confusion, depression) - causal relationship not established

Interactions

  • MAOIs (including moclobemide) - CNS excitation or depression manifesting as hypertension or hypotension; avoid concomitant use and for 14 days after an MAOI is discontinued
  • Tricyclic antidepressants - possible increased sedation
  • Antipsychotics - enhanced sedative and hypotensive effect
  • Ritonavir - avoid concomitant use as plasma concentration of meptazinol may be increased
  • Alcohol - enhanced sedative and hypotensive effect
  • Ciprofloxacin (quinolones) - avoid premedication with meptazinol as a reduced plasma ciprofloxacin concentration may be experienced
  • Anxiolytics and hypnotics - enhanced sedative effect
  • Metoclopramide or domperidone - may result in antagonism of gastro-intestinal side effects
  • Cimetidine - may inhibit metabolism of meptazinol, increasing its plasma concentration

Monitoring

  • Review the clinical need for analgesic treatment regularly; monitor closely for signs of misuse, abuse or addiction
  • Signs of tolerance: treatment less effective with chronic use and a need to increase the dose to obtain the same pain control
  • Drug withdrawal syndrome on abrupt cessation or dose reduction - taper gradually when therapy is no longer required
  • Caution in patients already severely compromised in respiratory function (a reduced dose may be appropriate); caution in hypotension, hypothyroidism, asthma (avoid during an attack), prostatic hypertrophy and convulsive disorders; safety in myocardial infarction has not been established
  • Hyperalgesia may be diagnosed if a patient on long-term opioid therapy presents with increased pain - symptoms may resolve with a reduction of opioid dose

Clinical monograph

How it works

It acts as a partial agonist at opioid receptors, with relative selectivity for a subtype, and also has central cholinergic activity, producing analgesia with a lower reported propensity for respiratory depression than full opioid agonists.

Prescribing in practice

  • As an opioid it can still cause respiratory depression, sedation, and dependence, and its partial-agonist action may precipitate withdrawal in patients dependent on full opioid agonists.
  • Nausea and vomiting are common adverse effects; an antiemetic may be required, particularly in obstetric use.
  • Use with caution in respiratory impairment, head injury, and hepatic or renal impairment; consult the SPC.

Monitoring

Monitor pain relief, level of sedation, respiratory rate, and for nausea, especially when combined with other central nervous system depressants.

Counselling the patient

  • This is a strong painkiller that may cause drowsiness, nausea, or dizziness.
  • Avoid alcohol and tell staff if you feel very sleepy or short of breath.
  • It is intended for short-term pain relief only.

Evidence & guidelines

Meptazinol is a long-established opioid analgesic for moderate pain, with its use and cautions described in standard UK prescribing references.

Reference: 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