The effects in overdosage will be potentiated by simultaneous ingestion of alcohol and psychotropic drugs.
Symptoms
Central nervous system depression, including respiratory depression, may develop but is unlikely to be severe unless other sedative agents have been co-ingested, including alcohol, or the overdose is very large. The pupils may be pin-point in size; nausea and vomiting are common. Hypotension and tachycardia are possible but unlikely.
Management
This should include general symptomatic and supportive measures including a clear airway and monitoring of vital signs until stable. Consider activated charcoal if an adult presents within one hour of ingestion of more than 350 mg or if more than 2.5 mg/kg (adults and children) has been ingested.
Give naloxone if coma or respiratory depression is present. Naloxone is a competitive antagonist and has a short half-life so large and repeated doses may be required in a seriously poisoned patient. Observe for at least four hours after ingestion, or eight hours if a sustained release preparation has been taken.
Suspected opiate abuse, known hypersensitivity to codeine or any of the other ingredients.
Liver or respiratory failure or patients at risk of paralytic ileus.
In patients with raised intracranial pressure or head injury.
In patients for whom it is known they are CYP2D6 ultra-rapid metabolisers.
During an acute asthma attack.
Children under 18 years of age.
In women during breastfeeding
None stated.
The following undesirable effects have been reported following use of codeine phosphate or opioid analgesics and may arise following use of this medicine. The frequency of adverse effects cannot be estimated from available data.
Psychiatric disorders: hallucinations, dysphoria, euphoria, mood changes, restlessness, confusion.
Nervous system disorders: dizziness, drowsiness, seizures, addiction, tolerance, dependence, headache, vertigo, malaise, sleep disturbances.
Eye disorders: miosis, visual disturbances.
Cardiac disorders: palpitations, bradychardia, tachycardia.
Vascular disorders: postural hypotension, hypothermia, facial flushing, oedema.
Respiratory, thoracic and mediastinal disorders: respiratory depression.
Gastrointestinal disorders: nausea, vomiting, constipation, abdominal pain, anorexia, pancreatitis, dry mouth.
Hepatobiliary disorders: biliary spasm.
Skin and subcutaneous tissue disorders: rashes, urticaria, pruritis, sweating.
Musculoskeletal and connective tissue disorders: muscle fasciculation or rigidity.
Renal and urinary disorders: difficulty with micturition, ureteric spasm or retention.
Reproductive system and breast disorders: decreased libido or potency.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard.
None stated
Codeine is indicated in adults for the relief of an unproductive dry cough.
RO5D A04 - Cough suppressants, excl. combinations with expectorants - opium alkaloids and derivatives
PMS-Codeine contains codeine phosphate which is an opiate with analgesic, anti-diarrhoeal and cough suppressant activities.
Codeine is a centrally acting weak analgesic. Codeine exerts its effect through µ opioid receptors, although codeine has low affinity for these receptors, and its analgesic effect is due to its conversion to morphine. Codeine, particularly in combination with other analgesics such as paracetamol, has been shown to be effective in acute nociceptive pain.
None stated.
This medicine should be used with caution in patients with renal and hepatic impairment (but avoid if severe), patients suffering from asthma or other respiratory disorders, or patients with a history of asthma, hypotension, shock, myasthenia gravis, cardiac arrhythmias, acute abdomen, gallstones, prostatic hypertrophy, urethral stenosis, obstructive or inflammatory bowel disorders, diseases of the biliary tract, and convulsive disorders.
Administration of pethidine and possibly other opioid analgesics to patients taking a monoamine oxidase inhibitor (MAOI) has been associated with very severe and sometimes fatal reactions. If the use of codeine is considered essential then great care should be taken in patients taking MAOIs or within 14 days of stopping MAOIs..
Use with caution in the elderly as codeine may contribute to faecal impaction, producing incontinence, spurious diarrhoea, abdominal pain and rarely colonic obstruction. Prolonged use could aggravate irritable bowel syndrome.
A reduced dose is recommended in elderly or debilitated patients, in hepatic and renal impairment (but avoid if severe), in hypothyroidism, and in adrenocortical insufficiency. Repeated use of opioid analgesics is associated with the development of psychological and physical dependence; although this is rarely a problem with therapeutic use, caution is advised if prescribing for patients with a history of drug dependence or in acute alcoholism.
This medicine and other cough suppressants may cause sputum retention and this may be harmful in patients with chronic bronchitis and bronchiectasis.
If symptoms persist consult your doctor.
CYP2D6 metabolism
Codeine is metabolised by the liver enzyme CYP2D6 into morphine, its active metabolite. If a patient has a deficiency or is completely lacking this enzyme an adequate analgesic effects will not be obtained. Estimates indicate that up to 7% of the Caucasian population may have this deficiency. However, if the patient is an extensive or ultra-rapid metaboliser there is an increased risk of developing side effects of opioid toxicity even at commonly prescribed doses. These patients convert codeine into morphine rapidly resulting in higher than expected serum morphine levels. General symptoms of opioid toxicity include nausea, vomiting, constipation, lack of appetite and somnolence. In severe cases this may include symptoms of circulatory and respiratory depression.
Estimates of prevalence of ultra-rapid metabolisers in different populations are summarized below:
| Population | Prevalence % |
| African/Ethiopian | 29% |
| African/American | 3.4% to 6.5% |
| Asian | 1.2% to 2% |
| Caucasian | 3.6% to 6.5% |
| Greek | 6.0% |
| Hungarian | 1.9% |
| Northern European | 1%-2% |
Precautions/warnings to be declared on labels:
Do not exceed the stated dose.
Keep out of the sight and reach of children.
It contains sodium hydroxybenzoates and sunset yellow dye which may cause allergic reactions (possibly delayed).
This medicine contains small amounts of ethanol (alcohol), less than 100mg per 10ml dose.
Using the dose recommended, this medicine is not considered to be a hazard. Nevertheless, use of codeine at higher doses or in more sensitive individuals may cause sedation, dizziness and nausea.Patients should be advised not to drive or operate machinery if affected by dizziness or sedation.
This medicine can impair cognitive function and can affect a patient's ability to drive safely. This class of medicine is in the list of drugs included in regulations under 5a of the Road Traffic Act 1988. When prescribing this medicine, patients should be told:
- The medicine is likely to affect your ability to drive
- Do not drive until you know how the medicine affects you
- It is an offence to drive while under the influence of this medicine
- However, you would not be committing an offence (called “statutory defenceâ€) if:
o The medicine has been prescribed to treat a medical or dental problem and
o You have taken it according to the instructions given by the prescriber and in the information provided with the medicine and
o It was not affecting your ability to drive safely
For oral administration.
Adult:
One 5ml spoonful four times daily.
Elderly:
Should be used with caution; a reduced dose can be recommended by a doctor.
Paediatric population
Codeine should not be used for the treatment of children under the age of 18 years.
None stated.
