Co-Dydramol Tablets
SUMMARY OF PRODUCT CHARACTERISTICS
1. NAME OF THE MEDICINAL PRODUCT
Co-dydramol Tablets
2 QUALITATIVE AND QUANTITATIVE COMPOSITION
Dihydrocodeine Tartrate BP 10.0 mg
Paracetamol BP 500.0 mg
3 PHARMACEUTICAL FORM
Tablet.
4. CLINICAL PARTICULARS
4.1. Therapeutic indications
a) As an analgesic.
b) As an antitussive.
4.2. Posology and method of administration
Codydramol tablets should be taken, if possible, during or after meals. As an analgesic:
Adults and children over 12 years: 1 tablet every four hours. This may if necessary be increased to 2 tablets four times daily.
As an antitussive:
Adults and children over 12 years: 1 tablet every four hours.
Not recommended for children under 12 years.
Dosage should be reduced in the elderly.
Do not exceed 8 tablets in 24 hours.
For oral administration.
4.3.
Contraindications
Hypersensitivity to either Paracetamol or codeine/DHC, or any of the excipients of Co-dydramol Tablets.
Severe renal or hepatic impairment.
Co-dydramol Tablets are contraindicated in patients for whom opiate medications are contraindicated. This will include some patients with acute asthma, obstructive airway disease, respiratory depression, acute alcoholism, head injuries, raised intracranial pressure and following biliary surgery.
4.4 Special warnings and precautions for use
Use with caution in the following conditions:
• impaired liver function (avoid if severe) and in chronic hepatic disease. The hazards of overdose are greater in those with noncirrhotic alcoholic liver disease. Prolonged use of co-dydramol may cause hepatic necrosis
• renal disease (avoid in severe renal impairment)
• hypothyroidism (risk of depression and prolonged CNS depression is increased, dose may need to be reduced.
• inflammatory bowel disease - risk of toxic megacolon
• convulsions - may be induced or exacerbated
• head injuries or conditions where increased intracranial pressure
• gall bladder disease or gall stones - opioids may cause biliary contraction
• acute abdominal conditions and gastro-intestinal surgery - use with caution after recent GI surgery as opioids may alter GI motility
• prostatic hypertrophy, urethral stricture or recent urinary tract surgery
• adrenocortical insufficiency, eg Addison’s disease
• hypotension and shock
• myasthenia gravis
• phaeochromocytoma - opioids may stimulate catecholamine release by inducing the release of endogenous histamine
• elderly or debilitated patients.
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 dihydrocodeine is considered essential then great care should be taken in patients taking MAOIs or within 14 days of stopping MAOIs (see section 4.5).
The risk-benefit of continued use should be assessed regularly by the prescriber.
Patients should be advised not to exceed the recommended dose and not to take other products containing paracetamol or opiate derivatives.
Patients should be advised to consult their doctor if symptoms persist for more than three days.
Tolerance to Dihydrocodeine can develop with continued use. The incidence of unwanted effects is dose related.
Keep all medicines out of the reach of children.
The leaflet (or combined label/leaflet) will state:
• Immediate medical advice should be sought in the event of an overdose, even if you feel well, because of the risk of delayed, serious liver damage.
• Do not take for longer than directed by your prescriber
• Taking codeine/dihydrocodeine (DHC) regularly for a long time can lead to addiction, which might cause you to feel restless and irritable when you stop taking the tablets.
• Taking a painkiller for headaches too often or for too long can make them worse.
• In the 'before taking' section, the leaflet will display: If you need to use this medicine for more than three days at a time, see your doctor, pharmacist or healthcare professional.
The label will state
• Do not take for longer than directed by you prescriber as taking codeine/DHC regularly for a long time can lead to addiction.
• Immediate medical advice should be sought in the event of an overdose, even if you feel well.
• The label will display prominently on outer pack - not boxed, If you need to use this medicine for more than three days at a time, see your doctor or pharmacist.
4.5. Interactions with other medicinal products and other forms of interaction
Paracetamol can interact with the following
• Drugs which alter gastric emptying time (eg cimetidine, ethyl alcohol, oral steroid contraceptives). These drugs reduce or delay peak paracetamol blood levels.
• Metoclopramide or domperidone increases the speed of absorption of paracetamol.
• Cholestyramine reduces paracetamol absorption.
• Drugs which interfere with the metabolism of paracetamol by competition with metabolic pathways or substrates eg anticonvulsants (phenytoin), hepatic enzyme inducers, alcohol, barbiturates, tricyclic antidepressants. A poor diet (low protein) may also have a similar effect on the risk of serious paracetamol toxicity to hepatic enzyme inducers. Patients who have taken barbiturates, tricyclic antidepressants and alcohol may show diminished ability to metabolise large doses of paracetamol, the plasma half-life of which may be prolonged.
• The anticoagulant effect of warfarin and other coumarins may be enhanced by prolonged regular use of paracetamol with increased risk of bleeding.
• Alcohol can increase the hepatotoxicity of paracetamol overdosage and may have contributed to the acute pancreatitis reported in one patient who had taken an overdosage of paracetamol.
Dihydrocodeine can interact with the following:
• CNS depressants - enhanced sedative and/or hypotensive effect with alcohol, anaesthetics, hypnotics, anxiolytics, antipsychotics, hydroxyzine, tricyclic antidepressants
• Antibacterials, eg ciprofloxacin, - avoid premedication with opioids as reduced plasma ciprofloxacin concentration
• MAOIs taken with pethidine have been associated with severe CNS excitation or depression (including hypertension or hypotension). Although this has not been documented with dihydrocodeine, it is possible that a similar interaction may occur and therefore the use of dihydrocodeine should be avoided while the patient is taking MAOIs and for 2 weeks after MAOI discontinuation.
• Antihistamines, Sedating- sedative effects possibly increased when opioid analgesics given with sedating antihistamines
• Mexiletine - delayed absorption
• Metoclopramide and domperidone - antagonise GI effects
• Cisapride - possible antagonism of GI effects
• Dopaminergics (eg selegiline) - possible risk of hyperpyrexia and CNS toxicity. This risk is greater with pethidine but with other opioids the risk is uncertain
Ulcer healing drugs - cimetidine inhibits the metabolism of opioid analgesics.
• Anticholinergics (eg atropine) - risk of severe constipation which may lead to paralytic illness, and/or urinary retention
• Antidiarrhoeal drugs (eg loperamide, kaolin) - increased risk of severe constipation
• Antihypertensive drugs (eg guanethidine, diuretics) - enhanced hypotensive effect
• Opioid antagonists (eg buprenorphine, naltrexone, naloxone)
• Neuromuscular blocking agents - additive respiratory depressant effects
4.6. Pregnancy and lactation
Epidemiological studies in human pregnancy have shown no effects due to paracetamol or dihydrocodeine. However, both drugs should be avoided during pregnancy unless considered essential by the physician.
Risk benefit must be considered because opioid analgesics cross the placenta. Regular use during pregnancy may cause physical dependence in the foetus leading to withdrawal syndromes in neonates. During labour opioids enter the foetal circulation and may cause respiratory depression in the neonate. Administration should be avoided during the late stages of labour and during the delivery of a premature infant.
Paracetamol is excreted in breast milk but not in a clinically significant amount. Available published data do not contraindicate breast feeding.
Dihydrocodeine may be present in breast milk in very low doses and is unlikely to adversely affect the breast fed infant.
4.7 Effects on ability to drive and use machines
Opioid analgesics can impair mental function and can cause blurred vision and drowsiness. Patients should make sure they are not affected before driving or operating machinery.
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 defence’) 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
4.8 Undesirable effects
At the recommended dosage, paracetamol may cause the following side effects:
Immune System Disorders- Hypersensitivity reactions, rare but may include skin rash, drug fever, mucosal lesions.
Effects on CNS - drowsiness, impaired mental functions
Effects on GI system - Chronic hepatic necrosis has been reported in a patient who took daily therapeutic doses of paracetamol for about a year, and liver damage has been reported after daily ingestion of excessive amounts for shorter periods. Acute pancreatitis has been reported. A review of a group of patients with chronic active hepatitis failed to reveal differences in the abnormalities of liver function in those who were long-term users of paracetamol, nor was the control of their disease improved after paracetamol withdrawal.
Effects on CVS - toxic myocarditis.
Effects on blood - methaemoglobinaemia, neutropenia, pancytopenia, leukopenia, thrombocytopenic purpura, haemolytic anaemia and agranulocytosis.
Effects on GU system - Nephrotoxicity following therapeutic doses of paracetamol is uncommon, but papillary necrosis has been reported after prolonged administration.
Other effects - Most reports of adverse reactions to paracetamol relate to overdosage with the drug.
Adverse effects of opioid treatment which have been reported include:
Immune System Disorders - including rash, urticaria (may be caused by histamine release)
Nervous System Disorders - confusion, drowsiness, vertigo, dizziness, changes in mood, hallucinations, CNS excitation (restlessness/excitement, Euphoria, dysphoria), convulsions, mental depression, headache, trouble sleeping, or nightmares, raised intracranial pressure, tolerance or dependence.
Gastrointestinal Disorders- constipation, abdominal pain, GI irritation, biliary spasm, nausea, vomiting, loss of appetite, dry mouth, paralytic ileus or toxic megacolon.
Cardiac Disorders - bradycardia, palpitations, hypotension.
Respiratory System disorder- respiratory depression, particularly in overdosage and in patients with compromised respiratory function, difficulty breathing
Skin and Subcutaneous Tissue Disorders-, increased sweating, redness or flushed face.
Eye Disorders- miosis, blurred or double vision.
Renal and Urinary Disorders - ureteral spasm, difficult micturition and urinary retention
Musculoskeletal and Connective Tissue Disorders- trembling
General and Administration Site Disorder - unusual tiredness or weakness, malaise, hypothermia.
Effects of withdrawal - Regular prolonged use of codeine/DHC is known to lead to addiction and abrupt withdrawal precipitates a withdrawal syndrome. Symptoms may include tremor, restlessness and irritability insomnia, nausea, vomiting, sweating and increase in heart rate, respiratory rate and blood pressure. NOTE - tolerance diminishes rapidly after withdrawal so a previously tolerated dose may prove fatal.
4.9. Overdose
Codeine
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 coingested, 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 a child more than 5 mg/kg.
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.
Paracetamol
Liver damage is possible in adults who have taken 10g or more of paracetamol. Ingestion of 5g or more of paracetamol may lead to liver damage if the patient has risk factors (see below).
Risk Factors:
If the patient
a, Is on long term treatment with carbamazepine, phenobarbitone, phenytoin, primidone, rifampicin, St John’s Wort or other drugs that induce liver enzymes.
Or
b, Regularly consumes ethanol in excess of recommended amounts.
Or
c, Is likely to be glutathione deplete e.g. eating disorders, cystic fibrosis, HIV infection, starvation, cachexia.
Symptoms
Symptoms of paracetamol overdosage in the first 24 hours are pallor, nausea, vomiting, anorexia and abdominal pain. Liver damage may become apparent 12 to 48 hours after ingestion. Abnormalities of glucose metabolism and metabolic acidosis may occur. In severe poisoning, hepatic failure may progress to encephalopathy, haemorrhage, hypoglycaemia, cerebral oedema, and death. Acute renal failure with acute tubular necrosis, strongly suggested by loin pain, haematuria and proteinuria, may develop even in the absence of severe liver damage. Cardiac arrhythmias and pancreatitis have been reported.
Management
Immediate treatment is essential in the management of paracetamol overdose. Despite a lack of significant early symptoms, patients should be referred to hospital urgently for immediate medical attention. Symptoms may be limited to nausea or vomiting and may not reflect the severity of overdose or the risk of organ damage. Management should be in accordance with established treatment guidelines, see BNF overdose section.
Treatment with activated charcoal should be considered if the overdose has been taken within 1 hour. Plasma paracetamol concentration should be measured at 4 hours or later after ingestion (earlier concentrations are unreliable). Treatment with N-acetylcysteine may be used up to 24 hours after ingestion of paracetamol, however, the maximum protective effect is obtained up to 8 hours post-ingestion. The effectiveness of the antidote declines sharply after this time. If required the patient should be given intravenous N-acetylcysteine, in line with the established dosage schedule. If vomiting is not a problem, oral methionine may be a suitable alternative for remote areas, outside hospital. Management of patients who present with serious hepatic dysfunction beyond 24h from ingestion should be discussed with the NPIS or a liver unit.
5 PHARMACOLOGICAL PROPERTIES
5.1 Pharmacodynamic properties
Dihydrocodeine tartrate is a potent analgesic with well defined anti-tussive properties.
Paracetamol has analgesic and anti-pyretic actions similar to those of aspirin but has no useful anti-inflammatory properties.
5.2. Pharmacokinetic Properties
The pharmacokinetics of dihydrocodeine may be similar to those of codeine; they differ between subjects with normal renal function and those with chronic renal failure treated with haemodialysis.
Dihydrocodeine is well absorbed from the gastrointestinal tract following oral administration, and a small quantity is bound to plasma proteins. Peak levels of plasma dihydrocodeine concentration are attained in an hour following ingestion. Plasma half-life has been reported to be 3-4 hours after oral ingestion. Dihydrocodeine is metabolised in the liver by O- and N-demethylation. Dihydrocodeine and its metabolites are excreted entirely by the kidneys mainly as conjugates with glucuronic acid.
Paracetamol is readily absorbed from the gastrointestinal tract with peak plasma concentration occurring 30 minutes to 2 hours after ingestion. It is metabolised in the liver and excreted in the urine mainly as the glucuronide and the sulphate conjugates. Less than 5% is excreted as unchanged paracetamol. The elimination half-life varies from 1 to 4 hours. Plasma-protein binding is negligible at usual therapeutic concentrations but increases with increasing concentrations. A minor hydroxylated metabolite which is usually produced in small amounts by mixed-function oxidases in liver and which is usually de-toxified by conjugation with liver glutathione may accumulate following paracetamol overdosage and may cause liver damage.
5.3. Preclinical Safety Data
Not applicable
6 PHARMACEUTICAL PARTICULARS
6.1 List of excipients
Starch, povidone (K=29/32), sodium starch glycollate, stearic acid, colloidal silicone dioxide, talc.
6.2. Incompatibilities
None stated
6.3. Shelf Life
1 year
6.4. Special Precautions for Storage
Store in a cool dry place protected from light below 25 °C.
6.5. Nature and Contents of Container
Securitainers containing 25, 50, 100, 250, 500 or 1000 tablets.
6.6. Instruction for Use/Handling
Not applicable
7 MARKETING AUTHORISATION HOLDER
Mercury Pharma (Generics) Ltd Capital House, 85 King William Street,
London EC4N 7BL, UK
8 MARKETING AUTHORISATION NUMBER(S)
PL 16201/0006
9 DATE OF FIRST AUTHORISATION/RENEWAL OF THE AUTHORISATION
06/03/2009
10 DATE OF REVISION OF THE TEXT
28/11/2014