Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Weak opioid analgesic

Dihydrocodeine

Brand names: DHC Continus (MR), DF118 Forte

Dihydrocodeine is a moderate opioid for moderate-to-severe pain; it is a controlled drug.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

DOSAGE AND ADMINISTRATION: The usual adult dosage is two (2) TREZIX™ (acetaminophen, caffeine, and dihydrocodeine bitartrate) capsules orally every four (4) hours, as needed. Dosage should be adjusted according to the severity of the pain and the response of the patient. No more than two (2) capsules should be taken in a 4-hour period. No more than five (5) doses, or ten (10) capsules should be taken in a 24-hour period.

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2022-05-02. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It is an opioid agonist (mainly at mu receptors); unlike codeine, its analgesia depends less on CYP2D6 conversion.

Prescribing in practice

  • Constipation, nausea and drowsiness are common; co-prescribe a laxative.
  • Reduce the dose in renal or hepatic impairment and in older or frail patients.
  • There is additive sedation and respiratory depression with other CNS depressants; counsel on dependence.

Monitoring

Review pain relief, bowel habit and signs of dependence.

Counselling the patient

  • It commonly causes constipation — take the laxative provided.
  • Do not combine it with alcohol or other sedatives.
  • Take it only as prescribed; it can be habit-forming.

Evidence & guidelines

A moderate-opioid option on the analgesic ladder for moderate-to-severe pain.

Reference: SmPC DHC Continus; NICE NG193 (chronic primary pain 2021); WHO Analgesic Ladder; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Drugs
Pathways