Compound analgesic (weak opioid + paracetamol) Pregnancy: Avoid 3rd trimester — neonatal opioid withdrawal syndrome. Earlier pregnancy: paracetamol alone preferred.

Co-codamol (codeine + paracetamol)

Brand names: Solpadol (30/500), Tylex (30/500), Kapake (30/500), Codipar, Solpadeine Max

Adult dose

Dose: 8/500 (OTC): 1–2 tablets up to QDS; max 8 tabs/day. 15/500 (POM): 1–2 tablets up to QDS; max 8 tabs/day. 30/500 (POM): 1–2 tablets up to QDS; max 8 tabs/day. ALWAYS check total paracetamol = 4 g/day max, and total codeine for the strength.

Route: Oral

Frequency: Up to four times daily

Max: Paracetamol 4 g/day; codeine 240 mg/day (8 × 30 mg)

Paracetamol 4 g/day MAX irrespective of strength — counsel about other paracetamol-containing OTC products (cold remedies). Reduce paracetamol to 3 g/day if weight <50 kg, malnourished, hepatic impairment, or alcohol use disorder.

Paediatric dose

Route: Oral

Frequency: Up to QDS

Codeine CONTRAINDICATED in <12 yrs (MHRA 2013 — death from respiratory depression in ultra-rapid CYP2D6 metabolisers). 12–18 yrs: avoid for post-tonsillectomy/adenoidectomy. Use ibuprofen + paracetamol; oral morphine if breakthrough analgesia needed under specialist care.

Dose adjustments

Renal

eGFR 10–50: 75% of dose. eGFR <10: 50% of dose; risk of accumulation of codeine-6-glucuronide.

Hepatic

Reduce paracetamol to 2–3 g/day in severe impairment. Avoid in decompensated liver disease.

Clinical pearls

Codeine is a CYP2D6 prodrug — ~7% of UK population are poor metabolisers (no analgesia), ~3% ultra-rapid (toxicity risk). Many patients describe ineffective analgesia from codeine.
Co-codamol 8/500 (OTC) provides minimal additional analgesia over plain paracetamol — much of the benefit is the paracetamol component. NICE NG193 (chronic primary pain 2021) recommends AGAINST opioids in chronic primary pain.
Counsel about hidden paracetamol in cold/flu remedies, OTC analgesics — easily exceeds 4 g/day MAX.
Constipation is the most common reason for discontinuation in chronic use — co-prescribe laxative (e.g., macrogol or senna) from outset.
Withdrawal from chronic use: taper by 10% every 1–2 weeks; restless legs, GI upset, sweating common.
For acute pain post-op: NSAID + paracetamol regular usually outperforms codeine + paracetamol with fewer side effects.

Contraindications

Children under 12 (codeine — MHRA Drug Safety Update 2013)
Children/adolescents 12–18 with sleep apnoea or post-tonsillectomy/adenoidectomy
Breastfeeding mothers (CYP2D6 ultra-rapid metabolisers — neonatal respiratory depression)
Acute severe asthma, respiratory depression
Paralytic ileus
Raised intracranial pressure or head injury
MAOI within 14 days
Known CYP2D6 ultra-rapid metaboliser
Severe hepatic impairment (paracetamol component)

Side effects

Constipation (common with codeine — co-prescribe laxative for regular use)
Nausea, vomiting
Drowsiness, dizziness
Respiratory depression (especially in CYP2D6 ultra-rapid metabolisers; with alcohol/benzodiazepines)
Dependence and tolerance — escalating use risk
Hepatotoxicity at supratherapeutic paracetamol doses
Pruritus
Urinary retention
Serotonin syndrome (with SSRIs, SNRIs, MAOIs — rare)

Interactions

Other opioids/CNS depressants/alcohol/benzodiazepines: additive sedation, fatal respiratory depression
MAOIs: serotonin syndrome — avoid 14 days
CYP2D6 inhibitors (paroxetine, fluoxetine, bupropion): ↓ codeine → morphine conversion → ↓ analgesic effect (codeine is a prodrug)
Warfarin: regular paracetamol >2 g/day for >4 days can ↑ INR — monitor
Isoniazid, rifampicin: ↑ paracetamol hepatotoxicity

Monitoring

Bowel function (constipation)
INR if on warfarin
Sedation in elderly
Review for ongoing need at 4 weeks (acute) or 3-monthly (chronic)

Reference: BNFc; BNF 90; BNF for Children 2024; MHRA Drug Safety Update Apr 2013 (codeine in children); NICE NG193 (chronic primary pain 2021); FDA Codeine Black Box Warning. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways