Symptoms
Cases of overdose have been reported with doses up to 2.5 g of ketoprofen. In most instances the symptoms observed have been benign and limited to lethargy, drowsiness, nausea, vomiting and epigastric pain. Headache, rarely diarrhoea, disorientation, excitation, coma, dizziness, tinnitus, fainting, occasionally convulsions may also occur. Adverse effects seen after overdose with propionic acid derivatives such as hypotension, bronchospasm and gastro-intestinal haemorrhage should be anticipated.
In cases of significant poisoning, acute renal failure and liver damage are possible.
If renal failure is present, haemodialysis may be useful to remove circulating medicinal product.
Therapeutic measures:
There are no specific antidotes to ketoprofen overdosages. In cases of suspected massive overdosages, a gastric lavage is recommended and symptomatic and supportive treatment should be instituted to compensate for dehydration, to monitor urinary excretion and to correct acidosis, if present.
Owing to the slow release characteristics of Dinalgen, it should be expected that ketoprofen will continue to be absorbed for up to 16 hours after ingestion.
Within one hour of ingestion, consideration should be given to administering activated charcoal in an attempt to reduce absorption of slowly-released ketoprofen.
Alternatively, in adults, gastric lavage, aimed at recovering pellets that may still be in the stomach, should be considered if the patient presents within 1 hour of ingesting a potentially toxic amount.
It should be possible to identify the pellets in the gastric contents. Correction of severe electrolyte abnormalities may need to be considered.
Good urine output should be ensured.
Renal and liver function should be closely monitored.
Patients should be observed for at least four hours after ingestion of potentially toxic amounts.
Frequent or prolonged convulsions should be treated with intravenous diazepam.
The benefit of gastric decontamination is uncertain.
Other measures may be indicated by the patient's clinical condition.
None stated
The following CIOMS frequency rating is used, when applicable:
Very common (> 1/10); common (> 1/100 to <1/10); uncommon (> 1/1,000 to < 1/100); rare (> 1/10,000 to < 1/1,000); very rare (< 1/10,000), not known (cannot be estimated from the available data).
The following adverse reactions have been reported with Ketoprofen in adults:
Blood and lymphatic system disorders
- rare: haemorrhagic anaemia, anaemia due to bleeding
- not known: agranulocytosis, thrombocytopenia, bone marrow failure, neutropenia
Immune system disorders
- rare: anaphylactic reactions (including shock)
Psychiatric disorders
- not known: mood altered
Nervous system disorders
- uncommon: headache, dizziness, somnolence
- rare: paraesthesia
Eye disorders
)- not known: optic neuritis
Ear and labyrinth disorders
- rare: tinnitus
Cardiac disorders
- not known: heart failure, oedema
Vascular disorders
- not known: hypertension, vasodilatation
Respiratory, thoracic and mediastinal disorders
- rare: asthma, asthmatic attack
- not known: bronchospasm (particularly in patients with known hypersensitivity to ASA and other NSAIDs), rhinitis, non-specific allergic reactions, dyspnoea
Gastrointestinal disorders
- common: dyspepsia, nausea, abdominal pain, vomiting
- uncommon: constipation, diarrhoea, flatulence, gastritis
- rare: stomatitis, peptic ulcer
- very rare: pancreatitis (very rare reports of pancreatitis have been noted with NSAIDs)
- not known: exacerbation of colitis and Crohn's disease, gastrointestinal haemorrhage and perforation, gastralgia, melaena, haematemesis
Hepatobiliary disorders
- rare: hepatitis, transaminases increased, elevated serum bilirubin due to hepatitis disorders
- not known: abnormal liver function, jaundice
Skin and subcutaneous disorders
- uncommon: rash, pruritis
- not known: photosensitivity reactions, alopecia, urticaria, angioedema, bullous eruption including Stevens-Johnson syndrome and toxic epidermal necrolysis, exfoliative and bullous dermatoses (including epidermal necrolysis, erythema multiforme), purpura
Renal and urinary disorders
- not known: renal failure acute, tubulointerstitial nephritis, nephritic syndrome, renal function tests abnormal
General disorders and administration site conditions
- uncommon: oedema, fatigue
- not known: headache, taste perversion
Investigations
- rare: weight increased
In all cases of major adverse effects Dinalgen should be withdrawn at once.
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 Yellow Card Scheme at: www.mhra.gov.uk/yellowcard
No additional data of relevance to the prescriber.
Ketoprofen overall has the properties of a potent non-steroidal anti-inflammatory agent. It has the following pharmacological effects:
Anti-inflammatory
It inhibits the development of carageenan-induced abscesses in rats at 1mg/kg, UV radiation induced erythema in guinea pigs at 6mg/kg. It is also a potent inhibitor of PGE2 and PFG2 synthesis in guinea pig and human chopped lung preparations.
Analgesic
Ketoprofen effectively reduced visceral pain in mice caused by phenyl benzoquinone or by bradykinin following p.o. Administration at about 6 mg/kg.
Antipyretic
Ketoprofen (2 and 6 mg/kg) inhibited hyperthermia caused by s.c injection of brewer's yeast in rats and, at 1 mg/kg hyperthermia caused by i.v. administration of anticoagulant vaccine to rabbits.
Ketoprofen at 10 mg/kg i.v. did not affect the cardiovascular, respiratory, central nervous system or autonomic nervous systems.
Ketoprofen is slowly but completely absorbed from Dinalgen capsules. Maximum plasma concentration occurs after 6 - 8 hours. It declines thereafter with a half-life of about 8 hours. There is no accumulation on continued daily dosing. Ketoprofen is very highly bound to plasma protein
Patients should be warned about the potential for somnolence, dizziness or convulsions, drowsiness, fatigue and visual disturbances and be advised not to drive or operate machinery if these symptoms occur.
None stated
