Dihydrocodein

Dihydrocodeine is a semi-synthetic opioid analgesic related to codeine. It is formed by chemically modifying codeine and acts as an agonist at the mu-opioid receptor to produce pain relief and, to a lesser extent, cough suppression. It is commonly used in some countries as part of analgesic formulations and in combinations for cough.

In medical use, dihydrocodeine is prescribed for moderate to moderately severe pain and, in some preparations, as an antitussive. It is often found in oral tablets or capsules and may be combined with acetaminophen (paracetamol) or other non-opioid analgesics. The exact formulations and approved indications vary by country and regulatory status.

Pharmacologically, oral dihydrocodeine is absorbed and provides analgesia within about 30 to 60 minutes, with a duration of several hours depending on formulation. It is metabolized in the liver, and an active metabolite contributes to its effect. Like other opioids, its use carries risks of tolerance, dependence, and withdrawal, and it can cause typical opioid-related side effects such as drowsiness, nausea, constipation, and respiratory depression in overdose. It should be used with caution in people with respiratory conditions, liver impairment, or a history of substance use disorder.

Regulatory status varies by country, but dihydrocodeine is generally a controlled substance available only by prescription. It may be subject to tighter controls due to potential misuse and the availability of safer alternatives. Contraindications include significant respiratory depression, acute asthma, and known hypersensitivity to opioids.