Dihydrocodeine Facts
Opioid;
Description
Dihydrocodeine (DHC) is a semi-synthetic opioid of the morphinan class. It activates mu-opioid receptors, suppressing pain signaling and slowing central nervous system activity.
Subjective effects include pain suppression, warmth, mild euphoria, sedation, and a quieting of anxiety. The experience is gentler than morphine — a mild, manageable calm rather than a deep, heavy opioid weight.
Dihydrocodeine produces physical and psychological dependence and carries toxicity comparable to low-dose morphine at equivalent doses.[1] The overdose risk is amplified by its active metabolite, dihydromorphine, which binds opioid receptors far more powerfully than the parent drug — rapid metabolizers face heightened danger at standard doses.[2]
Dose and durationby route · individual sensitivity varies
Starts in 30 – 60 minLasts 4 – 6 hoursAfter-effects 2 – 6 hours
Body and dependence
- Acute toxicity
- High
- Chronic toxicity
- Moderate
- Physical dependence
- Moderate
- Psychological dependence
- Moderate
- Withdrawal
- Moderate
- Compulsive redosing
- Moderate
Tolerance
- Builds
- Moderate
- Fully resets after
- 10.5 days
- Carries over to
- opioids
Effectslikely at a common dose
- Perception
- none likely · 4 possible, including Vestibular distortion, Visual acuity suppression
- Body
- Sedation;
Constipation; Pupil constriction; Pain suppression; +19 possible, including Respiratory depression, Dizziness, Motor control impairment - Thinking
- none likely · 15 possible, including Cognitive impairment, Information processing suppression, Decision impairment
- Feeling
- none likely · 4 possible
- Self
- none likely · 6 possible, including Craving, Communication suppression, Social disconnection
- Time
- none likely · 2 possible, including Temporal disorientation
Who shouldn't take it
Combinations62 recorded
Seek help immediately if
- Unresponsive / can't be woken, even to a firm sternal rub
- Slow, shallow, or stopped breathing
- Pinpoint pupils
- Blue/grey lips, fingertips, or skin (cyanosis)
- Limp body; pale, clammy skin
- Choking or gurgling sounds ("death rattle")
- Slow, erratic, or absent pulse
What to do
- Try to wake them — shout their name, firm sternal rub
- Call emergency services immediately
- Administer naloxone if available
- Give rescue breaths (or CPR if there is no pulse)
- Place them in the recovery position
- Stay with them; re-dose naloxone every 2–3 minutes if there is no response
- Reversal agent
- Naloxone (Narcan) — opioid antagonist. May require repeated doses; its effect can wear off before the opioid does.
With prompt naloxone and rescue breathing, reversal is usually rapid. Because naloxone can wear off before the opioid — especially with long-acting opioids (methadone) or high-potency ones (fentanyl) — a period of monitoring is needed even after the person revives.
988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE
References
- [1]^Prescrire International (2016) 'Weak' opioid analgesics. Codeine, dihydrocodeine and tramadol: no less risky than morphine — Prescrire International PMID:27042732
- [2]^Schmidt H, Vormfelde Sv, Klinder K, et al. (2002) Affinities of dihydrocodeine and its metabolites to opioid receptors — Pharmacology & Toxicology PMID:12420793