white → purple2
dose.wiki is still in beta. Entries may contain inaccuracies and/or lack citations. See our docs for more info.
WARNINGDANGER OF DEATH
High doses alone or ordinary doses in combination with other depressants can fatally stop breathing.
Dihydrocodeine
DHC, Drocode, Paracodeine, Parzone, DF-118
Dihydrocodeine is a semi-synthetic opioid analgesic1 of the morphinan class. Developed in Germany in 1908 and first marketed in 1911, it was originally created during efforts to find more effective antitussive medications to curb the spread of airborne diseases like tuberculosis. Slightly more potent than codeine, it is prescribed for moderate to severe paincitation needed, dyspnea, and cough suppression. It is commonly sold in combination formulations containing paracetamol or aspirin2, which pose additional overdose riskscitation needed if not accounted for.
Dosage & Duration
Dosage
Doses are population estimates that vary widely between individuals.
Threshold~50 mg
Light50-100 mg
Moderate100-150 mg
Strong150-200 mg
Heavy200+ mg
Bioavailability
~20%
When using combination products that contain dihydrocodeine alongside paracetamol (acetaminophen) or other active ingredients, cold water extraction may be employed to separate the opioid component and reduce exposure to potentially hepatotoxic doses of the additional substances.
Duration
Onset30-45 minutes
After Effects1-8 hours
Total3-4 hours
Half-life
~4 hours
Subjective Effects
Legacy content. A statistically backed ontology from Mindstate Design Labs is coming soon.
Effects vary widely by individual, dose, and context.
Physical
The physical effects of dihydrocodeine can be broken down into several components which progressively intensify proportional to dosage.
Cognitive
The cognitive effects of dihydrocodeine can be broken down into several components which progressively intensify proportional to dosage. The general head space of dihydrocodeine is described by many as one of intense euphoria, relaxation, anxiety suppression and pain relief.
Pharmacology
Pharmacodynamics
Dihydrocodeine exerts its analgesic effects primarily through agonist activity at μ-opioid receptors, with lesser contributions from κ-opioid and δ-opioid receptors. Its affinity at the δ-opioid receptor is approximately 5 to 50 times weaker than at the μ-opioid receptor,3 while its κ-opioid affinity is comparable to that of codeine and morphine. The parent compound is itself pharmacologically active and is considered the primary contributor to analgesia.
Pharmacokinetics
Dihydrocodeine has low oral bioavailability (approximately 20%)4, attributable to poor gastrointestinal absorption and extensive first-pass metabolism by the liver and intestinal wall. It is metabolized hepatically via CYP2D6 (O-demethylation to dihydromorphine)5 and CYP3A4 (N-demethylation to nordihydrocodeine),5 with additional glucuronide conjugation producing dihydrocodeine-6-glucuronide (DHC-6-G),5 which itself contributes to the overall analgesic effect. Due to this multidirectional metabolic pathway, CYP2D6 metabolizer status does not appear to significantly influence analgesia, as pain threshold and pupillary responses do not differ between poor and extensive metabolizers. The mean elimination half-life is approximately 4 hours,4 with linear pharmacokinetics and plasma clearance of roughly 300 mL/min.
Dangerous
Highest riskThese combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.
Unsafe
AvoidThere is considerable risk of physical harm when taking these combinations, they should be avoided where possible.
Caution
Use cautionThese combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.
Tolerance
Tolerance timelines are rules of thumb, not exact schedules, and vary widely between individuals and use patterns.
Full Tolerance
Tolerance develops with repeated use, as is characteristic of opioids. Physical dependence has been demonstrated to develop with continued administration.citation needed
Cross Tolerance
Opioids (dihydrocodeine has demonstrated cross-tolerance with other opioids and has historically been used to manage morphine withdrawal)
Harm Potential
Addiction & Dependence
Psychological
ModerateDihydrocodeine produces euphoria at higher-than-therapeutic doses and is commonly used recreationally. Psychological dependence develops with repeated use, as is characteristic of opioids.citation needed
Physical
HighPhysical dependence develops with repeated use.citation needed Dihydrocodeine has demonstrated cross-tolerance with other opioids and has historically been used to manage morphine withdrawal.
History & Culture
Discovery and Development
Dihydrocodeine is a semi-synthetic opioid that was developed in Germany in 1908 during a period of intensive research into more effective antitussive agents. This effort was motivated by the urgent need to limit the transmission of airborne infectious diseases, particularly tuberculosis, pertussis,…
Legality
By Country
Legal / decriminalized1
JapanLegal (regulated)麻薬及び向精神薬取締法 (Narcotics and Psychotropics Control Act), Articles 2(1), 2(5), 3, 20-24, 26-28 and Appendix 1 items 23 and 78(i); 医薬品、医療機器等の品質、有効性及び安全性の確保等に関する法律 (PMD Act), Article 36-11; MHLW Notification 医薬発0213第1号 (13 February 2026) implementing the current 指定濫用防止医薬品 designation effective 1 May 2026; MHLW cough-medicine approval notice 薬食審査発0325第5号 (25 March 2015).7891011
Japanese primary law expressly schedules dihydrocodeine, its esters and salts as narcotics in Appendix 1 item 23.7 A preparation at or below 1% DHC (10/1000) with no other Appendix 1 substance or cannabis falls under the item 78(i) household-narcotic exception, and MHLW approval guidance permits DHC phosphate in qualifying cold medicines only within the 10/1000 product-mass limit.78 Those product-level exceptions do not make dihydrocodeine generally unscheduled, and pure or higher-strength DHC remains subject to the narcotics licensing, possession, transfer and medical-channel controls. Since 1 May 2026, qualifying non-external OTC products containing DHC are also designated abuse-prevention medicines, requiring the strengthened pharmacist/registered-seller information and purchase checks.1112 Ordinary DHC is a controlled narcotic, while qualifying authorized OTC cough/cold preparations can be legally supplied without a prescription under formulation-specific medicine approval and the current abuse-prevention sales regime. OTC status does not apply to every Japanese cough syrup, every DHC salt, or every product presentation; the exact product's concentration, ingredients, authorization and dosage form remain decisive.
References
Source Pages
Citations
- National Library of Medicine. (2009-11-24). DailyMed - DIHYDROCODEINE BITARTRATE, ACETAMINOPHEN AND CAFFEINE tablet. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f3ddb645-028a-4c54-96b9-dbfecacf19bb1
- Sun Pharmaceutical Industries, Inc.. (2017-08-31). DailyMed - ASPIRIN, CAFFEINE, AND DIHYDROCODEINE BITARTRATE capsules. DailyMed. https://dailymed.nlm.nih.gov/dailymed/medguide.cfm?setid=5add9c2f-421d-44ec-952d-95c3ff0a31e41
- H. Schmidt, S. V. Vormfelde, K. Klinder, U. Gundert-Remy, C. H. Gleiter, G. Skopp, R. Aderjan, & U. Fuhr. (2002). Affinities of dihydrocodeine and its metabolites to opioid receptors. 91(2), 57-63. https://doi.org/10.1034/j.1600-0773.2002.910203.x1
- F. J. Rowell, R. A. Seymour, & M. D. Rawlins. (1983). Pharmacokinetics of intravenous and oral dihydrocodeine and its acid metabolites. 25(3), 419-424. https://doi.org/10.1007/bf010379581234
- Susanne Ammon, Ute Hofmann, Ernst-Ulrich Griese, Nadja Gugeler, & Gerd Mikus. (1999). Pharmacokinetics of dihydrocodeine and its active metabolite after single and multiple oral dosing. 48(3), 317-322. https://doi.org/10.1046/j.1365-2125.1999.00042.x123456
- Matthew D. Turner. (2023-03-29). "A Profound, Abiding Hatred": An Analysis of Hermann Goering's Alleged Morphine Addiction. Cureus, 15(3), Article e36865. https://doi.org/10.7759/cureus.368651
- 麻薬及び向精神薬取締法, current MHLW text, Article 2 and Appendix 1 item 23. mhlw.go.jp (n.d.). https://www.mhlw.go.jp/web/t_doc?dataId=81102000&dataType=0123456
- MHLW 薬食審査発0325第5号, かぜ薬の製造販売承認事務の取扱いについて. mhlw.go.jp (n.d.). https://www.mhlw.go.jp/web/t_doc?dataId=00tc0860&dataType=1&pageNo=112
- MHLW 医薬品・医療機器等安全性情報 No.365, OTC abuse-risk medicines. mhlw.go.jp (n.d.). https://www.mhlw.go.jp/content/11120000/000542417.pdf1
- MHLW 医薬発0213第1号, current 指定濫用防止医薬品 designation application notice. mhlw.go.jp (n.d.). https://www.mhlw.go.jp/web/t_doc?dataId=00tc9724&dataType=1&pageNo=11
Further Reading
Article Status
Step 1 · Automated synthesisAn autonomous workflow built by Josie Kins compiled this article's foundation from information published across the web.
- Step 2 · First-pass review
A first pass manual review and edit of article prose and copy has been performed by subject-matter expert Lyrea. This does not guarantee factual accuracy. An additional human review for each of this article's citations is yet to be performed.
- Step 3 · Citation reviewPending
No one has reviewed this article's citations yet. That second pass checks each claim against the source it cites.
Recent changes7 human edits · latest
Times are UTCNewest first
24 January 2026
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Suggest an edit
Spotted a mistake, an outdated claim, or something missing from the Dihydrocodeine article? Send the editors a private note. Feedback lands in a moderation queue and is never shown on the site.
Wish to give generalised feedback? You can do so here.