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Kinovexen 250 mg Gastro-Resistant Tablets – Summary of Product Characteristics (SmPC) for healthcare professionals

Last updated: · Text from the MHRA, as of · About this document

The Summary of Product Characteristics (SmPC) is written for healthcare professionals. Patients will find plain advice in the patient information leaflet: how to take, side effects, pregnancy and breast-feeding.

Medicine strength:
250 mg
Contains active substance:
ATC code:

Summary of Product Characteristics (SmPC) - Kinovexen 250 mg gastro-resistant tablets

1 NAME OF THE MEDICINAL PRODUCT

Kinovexen 250 mg Gastro-Resistant Tablets

(Naproxen)

2. QUALITATIVE AND QUANTITATIVE COMPOSITIONS:

Each enteric coated tablet contains 250 mg naproxen.

For full list of excipients, see section 6.1.

3 PHARMACEUTICAL FORM

Gastro-resistant tablets.

White colour, circular shaped biconvex enteric coated tablets debossed with “250” on one side and plain on the other side.

4 CLINICAL PARTICULARS

4.1 Therapeutic indications

Kinovexen Gastro-resistant tablets are indicated in adults (18 to 50 years) for the short term relief of muscle or joint pain (such as sprains and strains, inflammation caused by sporting injuries, lower back pain, neck pain, or pain in the wrists or feet) and period pain.

4.2 Posology and method of administration

Posology

For oral administration and short-term use only.

Undesirable effects may be minimised by using the lowest effective dose for the shortest duration necessary to control symptoms (see section 4.4).

If in adults the product is required for more than 3 days, or if the symptoms worsen the patient should consult a doctor.

Adults (18 - 50 years): Therapy should be started at the lowest recommended dose, especially in older people.

Acute musculoskeletal disorders and dysmenorrhea

On the first day 2 tablets (500 mg) should be taken initially and then one tablet (250 mg) after 6 to 8 hours if needed. On the second and third day, if needed, one tablet (250 mg) should be taken every 6 to 8 hours. Not more than 3 tablets to be taken per day. The maximum duration of continuous treatment is 3 days.

Older people

Studies indicate that although total plasma concentration of naproxen is unchanged, the unbound plasma fraction of naproxen is increased in older people. The implication of this finding for Kinovexen Gastro-resistant Tablets dosing is unknown. As with other drugs used in older people it is prudent to use the lowest effective dose and for the shortest possible duration as older people are more prone to adverse events. Kinovexen is not recommended for use in those aged over 50 years.

Paediatric Population

Kinovexen Gastro-resistant Tablets are not recommended for use in children under 18 years of age.

Renal/hepatic impairment

A lower dose should be considered in patients with renal or hepatic impairment. Naproxen is contraindicated in patients with baseline creatinine clearance less than 30 ml/minute because accumulation of naproxen metabolites has been seen in patients with severe renal failure or those on dialysis (see section 4.3).

Method of administration

For oral administration.

To be taken preferably with or after food.

Kinovexen Gastro-resistant tablets should be swallowed whole with water. Not to be broken or crushed.

4.3 Contraindications

Active or history of peptic ulceration or active gastrointestinal bleeding (two or more distinct episodes of proven ulceration or bleeding). History of gastrointestinal bleeding or perforation, related to previous NSAIDs therapy.

Hypersensitivity to naproxen or any of the excipients. Since the potential exists for cross-sensitivity reactions, Kinovexen Gastro-resistant Tablets should not be given to patients in whom aspirin or other non-steroidal anti-inflammatory/analgesic drugs induce asthma, rhinitis, nasal polyps or urticaria. These reactions have the potential of being fatal. Severe anaphylactic-like reactions to naproxen have been reported in such patients.

Severe heart failure, hepatic or renal failure.

Naproxen is contraindicated during the last trimester of pregnancy (see section 4.6 – Pregnancy and lactation).

4.4 Special warnings and precautions for use

Undesirable effects may be minimised by using the lowest effective dose for the shortest duration necessary to control symptoms (see section 4.2 and GI and cardiovascular risks below). Kinovexen Gastro-resistant Tablets is for short-term use only.

Older people and/or debilitated patients are particularly susceptible to the adverse effects of NSAIDs, especially gastrointestinal bleeding and perforation, which may be fatal. Prolonged use of NSAIDs in these patients is not recommended. Kinovexen Gastro-resistant Tablets is not recommended for use in those aged over 50 years.

The anti-inflammatory and antipyretic activities of naproxen may reduce inflammation and fever, thereby diminishing their utility as diagnostic signs.

Bronchospasm may be precipitated in patients suffering from, or with a history of,

bronchial asthma or allergic disease.

As with other non-steroidal anti-inflammatory drugs, elevations of one or more liver function tests may occur. Hepatic abnormalities may be the result of hypersensitivity rather than direct toxicity. Severe hepatic reactions, including jaundice and hepatitis (some cases of hepatitis have been fatal) have been reported with this drug as with other non-steroidal anti- inflammatory drugs. Cross reactivity has been reported.

Naproxen decreases platelet aggregation and prolongs bleeding time. This effect should be kept in mind when bleeding times are determined.

Although sodium retention has not been reported in metabolic studies, it is possible that patients with questionable or compromised cardiac function may be at a greater risk when taking Kinovexen Gastro-resistant Tablets.

The product should not be taken, except on the advice of a doctor, by women who

first experience period pain more than a year after starting menstruation.

Gastrointestinal bleeding, ulceration and perforation

GI bleeding, ulceration or perforation, which can be fatal, has been reported with all NSAIDs at anytime during treatment, with or without warning symptoms or a previous history of serious GI events.

The risk of GI bleeding, ulceration or perforation is higher with increasing NSAID doses, in patients with a history of ulcer, particularly if complicated with haemorrhage or perforation (see section 4.3), and in older people.

Kinovexen Gastro-resistant Tablets should not be used in patients receiving concomitant medications which could increase the risk of ulceration or bleeding, such as oral corticosteroid, anticoagulants such as warfarin, selective serotonin-reuptake inhibitors or anti-platelet agents such as aspirin (see Section 4.5).

When GI bleeding or ulceration occurs in patients receiving Kinovexen Gastro-resistant Tablets, the treatment should be withdrawn.

NSAIDs should be given with care to patients with a history of gastrointestinal disease (ulcerative colitis, Crohn’s disease) as these conditions may be exacerbated (see Section 4.8).

Renal Effects

There have been reports of impaired renal function, renal failure, acute interstitial nephritis, haematuria, proteinuria, renal papillary necrosis and occasionally nephrotic syndrome associated with naproxen.

Renal failure linked to reduced prostaglandin production

The administration of an NSAID may cause a dose dependent reduction in prostaglandin formation and precipitate renal failure. Patients at greatest risk of this reaction are those with impaired renal function, cardiac impairment, liver dysfunction, those taking diuretics, angiotensin converting enzyme inhibitors, angiotensin-II receptor antagonists and older people. Renal function should be monitored in these patients (see also Section 4.3).

Use in patients with impaired renal function

As naproxen is eliminated to a large extent (95%) by urinary excretion via glomerular filtration, it should be used with great caution in patients with impaired renal function and the monitoring of serum creatinine and/or creatinine clearance is advised and patients should be adequately hydrated. Naproxen is contraindicated in patients having a baseline creatinine clearance of less than 30ml/minute.

Haemodialysis does not decrease the plasma concentration of naproxen because of the high degree of protein binding.

Certain patients, specifically those whose renal blood flow is compromised, such as in extracellular volume depletion, cirrhosis of the liver, sodium restriction, congestive heart failure, and pre-existing renal disease, should have renal function assessed before and during Kinovexen Gastro-resistant Tablets therapy. Some older people in whom impaired renal function may be expected, as well as patients using diuretics, may also fall within this category. A reduction in daily dosage should be considered to avoid the possibility of excessive accumulation of naproxen metabolites in these patients.

Use in patients with impaired liver function.

Chronic alcoholic liver disease and probably also other forms of cirrhosis reduce the total plasma concentration of naproxen, but the plasma concentration of unbound naproxen is increased. The implication of this finding for Kinovexen Gastro-resistant Tablets dosing is unknown but it is prudent to use the lowest effective dose.

Haematological

Patients who have coagulation disorders or are receiving drug therapy that interferes with haemostasis should be carefully observed if naproxen- containing products are administered.

Patients at high risk of bleeding or those on full anti-coagulation therapy (e.g. dicoumarol derivatives) may be at increased risk of bleeding if given naproxen- containing products concurrently.

Anaphylactic (anaphylactoid) reactions

Hypersensitivity reactions may occur in susceptible individuals. Anaphylactic (anaphylactoid) reactions may occur both in patients with and without a history of hypersensitivity or exposure to aspirin, other non- steroidal anti-inflammatory drugs or naproxen-containing products. They may also occur in individuals with a history of angio-oedema, bronchospastic reactivity (e.g. asthma), rhinitis and nasal polyps.

Anaphylactoid reactions, like anaphylaxis, may have a fatal outcome.

Steroids

Patients taking steroids should not take Kinovexen Gastro-resistant Tablets except under supervision of a doctor. If steroid dosage is reduced or eliminated during therapy, the steroid dosage should be reduced slowly and the patients must be observed closely for any evidence of adverse effects, including adrenal insufficiency and exacerbation of symptoms of arthritis.

Ocular effects

Studies have not shown changes in the eye attributable to naproxen administration. In rare cases, adverse ocular disorders including papillitis, retrobulbar optic neuritis and papilloedema, have been reported in users of NSAIDs including naproxen, although a cause and-effect relationship cannot be established; accordingly, patients who develop visual disturbances during treatment with naproxen-containing products should have an ophthalmological examination.

Cardiovascular and cerebrovascular effects

Patients with a history of hypertension and/or mild to moderate congestive heart failure should not take naproxen except under supervision of a doctor as fluid retention and oedema have been reported in association with NSAID therapy.

Clinical trial and epidemiological data suggest that use of coxibs and some NSAIDs (particularly at high doses and in long term treatment) may be associated with a small increased risk of arterial thrombotic events (for example myocardial infarction or stroke). Although data suggest that the use of naproxen (1000 mg daily) may be associated with a lower risk, some risk cannot be excluded.

Patients with uncontrolled hypertension, congestive heart failure, established ischaemic heart disease, peripheral arterial disease, and/or cerebrovascular disease should only be treated with naproxen under medical supervision. Similar consideration should be made before initiating longer-term treatment of patients with risk factors for cardiovascular events (e.g. hypertension, hyperlipidaemia, diabetes mellitus, smoking).

SLE and mixed connective tissue disease

In patients with systemic lupus erythematosus (SLE) and mixed connective tissue disorders there may be an increased risk of aseptic meningitis (see Section 4.8).

Dermatological

Serious skin reactions, some of them fatal, including exfoliative dermatitis, Stevens- Johnson syndrome, and toxic epidermal necrolysis, have been reported very rarely in association with the use of NSAIDs (see 4.8). Patients appear to be at highest risk for these reactions early in the course of therapy: the onset of the reactions occurring in the majority of cases within the first month of treatment. Kinovexen Gastro-resistant Tablets should be discontinued at the first appearance of skin rash, mucosal lesions, or any other sign of hypersensitivity.

Combination with other NSAIDs

The combination of naproxen-containing products and other NSAIDs, including cyclooxygenase-2 selective inhibitors, is not recommended, because of the cumulative risks of inducing serious NSAID-related adverse events.

Masking of symptoms of underlying infections

Kinovexen Gastro-resistant Tablets can mask symptoms of infection, which may lead to delayed initiation of appropriate treatment and thereby worsening the outcome of the infection. This has been observed in bacterial community acquired pneumonia and bacterial complications to varicella. When Kinovexen Gastro-resistant Tablets is administered for fever or pain relief in relation to infection, monitoring of infection is advised. In non-hospital settings, the patient should consult a doctor if symptoms persist or worsen.

Severe cutaneous adverse reactions (SCARs)

Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN), and drug

reaction with eosinophilia and systemic symptoms (DRESS), which can be life threatening or fatal, have been reported post-marketing in association with Kinovexen Gastro-resistant Tablets treatment. If signs and symptoms suggestive of these reactions appear, Kinovexen Gastro-resistant Tablets should be withdrawn

immediately. If the patient has developed SJS, or TEN or DRESS with the use of

Kinovexen Gastro-resistant Tablets, treatment with Kinovexen Gastro-resistant Tablets must not be restarted and should be permanently discontinued.

Excipients

Sodium

This medicine contains less than 1 mmol sodium (23 mg) per film-coated tablet, that is to say essentially ‘sodium-free’.

4.5 Interaction with other medicinal products and other forms of interaction

Kinovexen Gastro-resistant Tablets should not be taken with other medication except on the advice of a doctor, pharmacist or nurse.

Care should be taken in patients treated with any of the following drugs as interactions have been reported in some patients.

Concomitant administration of antacid or colestyramine can delay the absorption of naproxen but does not affect its extent. Concomitant administration of food can delay the absorption of naproxen but does not affect its extent.

Due to the high plasma protein binding of naproxen, patients simultaneously receiving hydantoins, anticoagulants, other NSAIDs, aspirin or a highly protein bound sulfonamide should be observed for signs of overdosage of these drugs.

Patients simultaneously receiving Kinovexen 250 mg Gastro-resistant Tablets and a hydantoin, sulfonamide or sulfonylurea should be observed for adjustment of dose if required.

It is considered unsafe to take NSAIDs in combination with anti-coagulants such as warfarin or heparin unless under direct medical supervision, as NSAIDs may enhance the effects of anti-coagulants (see section 4.4).

Acetylsalicylic acid:

Clinical pharmacodynamic data suggest that concomitant naproxen usage for more than one day consecutively may inhibit the effect of low-dose acetylsalicylic acid on platelet activity and this inhibition may persist for up to several days after stopping naproxen therapy. The clinical relevance of this interaction is not known.

Other analgesics including cyclooxygenase-2 selective inhibitors: Avoid concomitant use of two or more NSAIDs (including aspirin) as this may increase the risk of adverse effects (see Section 4.4).

No interactions have been observed in clinical studies with naproxen and anticoagulants or sulphonylureas, but caution is nevertheless advised since interaction has been seen with other non-steroidal agents of this class.

Caution is advised when Kinovexen Gastro-resistant Tablets is coadministered with diuretics as there can be a decreased diuretic effect. The natriuretic effect of furosemide has been reported to be inhibited by some drugs of this class. Diuretics can increase the risk of nephrotoxicity of NSAIDs.

Inhibition of renal lithium clearance leading to increases in plasma lithium concentrations has also been reported.

Kinovexen Gastro-resistant Tablets and other non-steroidal anti-inflammatory drugs can reduce the anti-hypertensive effect of anti-hypertensives. Concomitant use of NSAIDs with ACE-inhibitors or angiotensin-II receptor antagonists may increase the risk of renal impairment, especially in patients with pre-existing poor renal function (see section 4.4).

Probenecid given concurrently increases naproxen plasma levels and extends its half-life considerably.

Caution is advised where methotrexate is administered concurrently because of possible enhancement of its toxicity, since naproxen, in common with other nonsteroidal anti-inflammatory drugs, has been reported to reduce the tubular secretion of methotrexate in an animal model.

NSAIDs may exacerbate cardiac failure, reduce GFR and increase plasma cardiac glycoside levels when co-administered with cardiac glycosides.

As with all NSAIDs caution is advised when ciclosporin is co-administered because of the increased risk of nephrotoxicity.

NSAIDs should not be used for 8-12 days after mifepristone administration as NSAIDs can reduce the effect of mifepristone.

As with all NSAIDs, caution should be taken when co-administering with corticosteroids because of the increased risk of gastrointestinal ulceration or bleeding.

Animal data indicate that NSAIDs can increase the risk of convulsions associated with quinolone antibiotics. Patients taking quinolones may have an increased risk of developing convulsions.

There is an increased risk of gastrointestinal bleeding (see Section 4.4) when antiplatelet agents and selective serotonin reuptake inhibitors (SSRIs) are combined with NSAIDs.

There is a possible risk of nephrotoxicity when NSAIDs are given with tacrolimus.

There is an increased risk of haematological toxicity when NSAIDs are given with zidovudine. There is evidence of an increased risk of haemarthroses and haematoma in HIV (+) haemophiliacs receiving concurrent treatment with zidovudine and ibuprofen.

It is suggested that Kinovexen Gastro-resistant Tablets therapy be temporarily discontinued 48 hours before adrenal function tests are performed, because naproxen may artifactually interfere with some tests for 17-ketogenic steroids. Similarly, naproxen may interfere with some assays of urinary 5-hydroxy-indoleacetic acid.

4.6 Fertility, pregnancy and lactation

Pregnancy

Inhibition of prostaglandin synthesis may adversely affect the pregnancy and/or the embryo/foetal development. Data from epidemiological studies suggest an increased risk of miscarriage and of cardiac malformation and gastroschisis after use of a prostaglandin synthesis inhibitor in early pregnancy. The absolute risk for cardiovascular malformation was increased from less than 1%, up to approximately 1.5 %. The risk is believed to increase with dose and duration of therapy. In animals, administration of a prostaglandin synthesis inhibitor has been shown to result in increased pre- and post-implantation loss and embryo-foetal lethality. In addition, increased incidences of various malformations, including cardiovascular, have been reported in animals given a prostaglandin synthesis inhibitor during the organogenetic period.

From the 20th week of pregnancy onward, Kinovexen use may cause oligohydramnios resulting from foetal renal dysfunction. This may occur shortly after treatment initiation and is usually reversible upon discontinuation. In addition, there have been reports of ductus arteriosus constriction following treatment in the second trimester, most of which resolved after treatment cessation. Therefore, during the first and second trimester of pregnancy, Kinovexen Gastro-resistant Tablets should not be given unless clearly necessary. If Kinovexen Gastro-resistant Tablets is used by a woman attempting to conceive, or during the first and second trimester of pregnancy, the dose should be kept as low and duration of treatment as short as possible. Antenatal monitoring for oligohydramnios and ductus arteriosus constriction should be considered after exposure to naproxen for several days from gestational week 20 onward. Kinovexen Gastro-resistant Tablets should be discontinued if oligohydramnios or ductus arteriosus constriction are found.

During the third trimester of pregnancy, all prostaglandin synthesis inhibitors may expose the foetus to:

  • cardiopulmonary toxicity (with premature constriction/closure of the ductus arteriosus and pulmonary hypertension)
  • renal dysfunction, (see above)

the mother and the neonate, at the end of pregnancy, to:

  • possible prolongation of bleeding time, an anti-aggregating effect which may occur even at very low doses
  • inhibition of uterine contractions resulting in delayed or prolonged labour.

Consequently, Kinovexen Gastro-resistant Tablets is contraindicated during the third trimester of pregnancy.

Congenital abnormalities have been reported in association with NSAID administration in man; however, these are low in frequency and do not appear to follow any discernible pattern. As with other drugs of this type, naproxen produces delay in parturition in animals and also affects the human foetal cardiovascular system (closure of ductus arteriosus). Use of Kinovexen Gastro-resistant Tablets in the last trimester of pregnancy is contraindicated (see Section 4.3). NSAIDs should not be used during the first two trimesters of pregnancy, unless the potential benefit to the patient outweighs the potential risk to the foetus.

Labour and delivery

Naproxen containing products are not recommended in labour and delivery because, through its prostaglandin synthesis inhibitory effect, naproxen may adversely affect foetal circulation and inhibit contractions, with an increased bleeding tendency in both mother and child.

Breast-feeding

Naproxen has been found in the milk of lactating women. The use of naproxen should therefore be avoided in patients who are breast feeding.

Fertility

The use of naproxen, as with any drug known to inhibit

cyclooxygenase/prostaglandin synthesis, may impair fertility and is not recommended in women attempting to conceive. In women who have difficulty conceiving or are undergoing investigation of infertility, withdrawal of naproxen should be considered.

4.7 Effects on ability to drive and use machines

Some patients may experience drowsiness, dizziness, vertigo, insomnia, fatigue, visual disturbances or depression with the use of Kinovexen Gastro-resistant Tablets. If patients experience these or similar undesirable effects, they should not drive or operate machinery.

4.8 Undesirable effects

The following adverse events have been reported with NSAIDs and with naproxen.

Gastrointestinal disorders: The most commonly observed adverse events are gastrointestinal in nature. Nausea, vomiting, diarrhoea, flatulence, constipation, dyspepsia, abdominal discomfort, heartburn and epigastric distress. More serious reactions which may occur are gastro-intestinal bleeding, which is sometimes fatal, particularly in the elderly (see section 4.4), inflammation, ulceration, perforation, and obstruction of the upper and lower gastrointestinal tract, melaena, haematemesis, stomatitis, exacerbation of ulcerative colitis and Crohn’s disease (See section 4.4) and oesophagitis, gastritis and pancreatitis.

Blood and lymphatic system disorders: Neutropenia, thrombocytopenia, granulocytopenia including agranulocytosis, eosinophilia, leucopenia, aplastic anaemia and haemolytic anaemia.

Immune system disorders: Hypersensitivity reactions have been reported following treatment with NSAIDs in patients with, or without, a history of previous hypersensitivity reactions to NSAIDs. These may consist of (a) non- specific allergic reactions and anaphylaxis (b) respiratory tract reactivity comprising asthma, aggravated asthma, bronchospasm or dyspnoea, or (c) assorted skin disorders, including rashes of various types, pruritus, urticaria, purpura, angio-oedema and more rarely exfoliative and bullous dermatoses (including epidermal necrolysis and erythema multiforme).

Metabolic and nutrition disorders: hyperkalaemia.

Psychiatric disorders: Insomnia, dream abnormalities, depression, confusion and hallucinations.

Nervous system disorders: Convulsions, dizziness, headaches, light-headedness, drowsiness, paraesthesia, retrobulbar optic neuritis, inability to concentrate and cognitive dysfunction have been reported. Aseptic meningitis (especially in patients with existing autoimmune disorders, such as systemic lupus erythematosus, mixed connective tissue disease), with symptoms such as stiff neck, headache, nausea, vomiting, fever or disorientation (see section 4.4).

Eye Disorders: Visual disturbances, corneal opacity, papillitis and papilloedema.

Ear and Labyrinth disorders: Tinnitus, hearing disturbances including impairment and vertigo.

Cardiac disorders: Oedema, palpitations, cardiac failure and congestive heart failure have been reported.

Clinical trial and epidemiological data suggest that use of coxibs and some NSAIDs (particularly at high doses and in long term treatment) may be associated with a small increased risk of arterial thrombotic events (for example myocardial infarction or stroke) (see section 4.4).

Vascular disorders: Hypertension, vasculitis.

Respiratory, thoracic and mediastinal disorders: Dyspnoea, asthma, eosinophilic pneumonitis and pulmonary oedema.

Hepatobiliary disorders: Jaundice, fatal hepatitis and abnormal liver function tests.

Skin and subcutaneous tissue disorders: Skin rashes including fixed drug eruption, itching (pruritus), urticaria, ecchymoses, purpura, sweating.

Alopecia, erythema multiforme, Stevens Johnson syndrome, erythema nodosum, lichen planus, pustular reaction, SLE, epidermal necrolysis, very rarely toxic epidermal necrolysis, photosensitivity reactions (including cases in which skin resembles porphyria cutanea tarda “pseudoporphyria”) or epidermolysis bullosa-like reactions which may occur rarely.

If skin fragility, blistering or other symptoms suggestive of pseudoporphyria occur, treatment should be discontinued and the patient monitored.

Drug reaction with eosinophilia and systemic symptoms (DRESS) (see section 4.4) (Frequency: Not known)

Musculoskeletal and connective tissue disorders: Myalgia and muscle weakness.

Renal and urinary disorders: Including, but not limited to, glomerular nephritis, interstitial nephritis, nephrotic syndrome, haematuria, raised serum creatinine, renal papillary necrosis and renal failure.

Reproductive system and breast disorders: Female infertility.

General disorders and administration site conditions: Thirst, pyrexia, fatigue and malaise.

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 or search for MHRA Yellow card in the Google Play or Apple App Store.

4.9 Overdose

Symptoms

Symptoms include headache, heartburn, nausea, vomiting, epigastric pain, gastrointestinal bleeding, rarely diarrhoea, disorientation, excitation, drowsiness, dizziness, tinnitus, fainting. In cases of significant poisoning acute renal failure and liver damage are possible.

Respiratory depression and coma may occur after the ingestion of NSAIDs but are rare.

In one case of naproxen overdose, transient prolongation of the prothrombin time due to hypothrombinaemia may have been due to selective inhibition of the synthesis of vitamin- K dependent clotting factors.

A few patients have experienced seizures, but it is not known whether these were naproxen-related or not. It is not known what dose of the drug would be life threatening.

Management

Patients should be treated symptomatically as required. Within one hour of ingestion of a potentially toxic amount activated charcoal should be considered. Alternatively in adults gastric lavage should be considered within one hour of ingestion of a potentially life- threatening overdose.

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. Other measures may be indicated by the patient’s clinical condition.

Haemodialysis does not decrease the plasma concentration of naproxen because of the high degree of protein binding. However, haemodialysis may still be appropriate in a patient with renal failure who has taken naproxen.

5 PHARMACOLOGICAL PROPERTIES

5.1 Pharmacodynamic properties

Pharmacotherapeutic group: Anti-inflammatory and antirheumatic products, nonsteroids.

ATC code: M01AE02

Naproxen has been shown to have anti-inflammatory, analgesic and antipyretic properties when tested in classical animal test systems. It exhibits its anti-inflammatory effect even in adrenalectomised animals, indicating that its action is not mediated through the pituitary- adrenal axis. It inhibits prostaglandin synthetase, as do other non-steroidal anti- inflammatory agents. As with other agents, however, the exact mechanism of its anti- inflammatory action is not known.

5.2 Pharmacokinetic properties

Naproxen is fully absorbed from the gastro-intestinal tract. and peak plasma levels are reached in 2 to 4 hours. Naproxen is present in the blood mainly as unchanged drug, extensively bound to plasma proteins. The plasma half-life is between 12 and 15 hours, enabling a steady state to be achieved within 3 days of initiation of therapy on a twice daily dose regimen. The degree of absorption is not significantly affected by either foods or most antacids. Excretion is almost entirely via the urine, mainly as conjugated naproxen, with some unchanged drug. Metabolism in children is similar to that in adults. Chronic alcoholic liver disease reduces the total plasma concentration of naproxen but the concentration of unbound naproxen increases. In the elderly, the unbound plasma concentration of naproxen is increased although total plasma concentration is unchanged.

When naproxen is administered in the enteric-coated form, the peak plasma levels are delayed when compared with the standard tablets. However, the mean areas under the plasma concentration time curves, and hence bioavailability, are equivalent. The tablets, therefore, perform as one would anticipate for a drug which does not disintegrate until it reaches the small intestine, where dissolution is rapid and complete.

5.3 Preclinical safety data

Carcinogenicity

Naproxen was administered with food to Sprague-Dawley rats for 24 months at doses of 8, 16 and 24mg/kg/day. Naproxen was not carcinogenic in rats.

Mutagenicity

Mutagenicity was not seen in Salmonella typhimurium (5 cell lines), Sachharomyces cerevisisae (1 cell line) and mouse lymphoma tests.

Fertility

Naproxen did not affect the fertility of rats when administered orally at doses of 30mg/kg/day to males and 20mg/kg/day to females.

Teratogenicity

Naproxen was not teratogenic when administered orally at doses of 20mg/kg/day during organogenesis to rats and rabbits.

Perinatal/Postnatal Reproduction

Oral administration of naproxen to pregnant rats at doses of 2, 10 and 20mg/kg/day during the third trimester of pregnancy resulted in difficult labour. These are known effects of this class of compounds and were demonstrated in pregnant rats with aspirin and indometacin.

6 PHARMACEUTICAL PARTICULARS

6.1 List of excipients

Microcrystalline Cellulose

Croscarmellose sodium

Povidone Magnesium stearate

Methacrylic acid ethylacrylate copolymer (1:1) dispersion 30% Sodium hydroxide

Triethyl citrate

Talc

6.2 Incompatibilities

None

6.3 Shelf life

36 months

6.4 Special precautions for storage

This medicinal product does not require any special storage conditions

6.5 Nature and contents of container:

White opaque PVC/Aluminium foil blister of 9 tablets in a carton

6.6 Special precautions for disposal

Any unused medicinal product or waste material should be disposed of in accordance with local requirements.

7 MARKETING AUTHORISATION HOLDER

NOUMED LIFE SCIENCES LIMITED

Noumed House,

Shoppenhangers Road,

Maidenhead, Berkshire,

SL6 2RB,

United Kingdom

8 MARKETING AUTHORISATION NUMBER(S)

PL 44041/0199

9 DATE OF FIRST AUTHORISATION/RENEWAL OF THE

AUTHORISATION

23/11/2021

10 DATE OF REVISION OF THE TEXT

24/09/2026

About this document

Source: MHRA - Medicines and Healthcare products Regulatory Agency (products.mhra.gov.uk) · Marketing authorisation: PL 44041/0199

Last revision stated in the text: 24 September 2026 · MHRA data as of 13 October 2026

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The information on this site does not replace the advice of a doctor or pharmacist.

Facts about Kinovexen 250 mg gastro-resistant tablets

Active substance Naproxen
Strength 250 mg
Pharmaceutical form White colour, circular shaped biconvex enteric coated tablets debossed with “250” on one side and plain on the other side.
Excipients Microcrystalline Cellulose, Croscarmellose sodium, Povidone Magnesium stearate, Methacrylic acid ethylacrylate copolymer (1:1) dispersion 30% Sodium hydroxide, Triethyl citrate, Talc
Shelf life 36 months
Storage This medicinal product does not require any special storage conditions
Drug group (ATC) Anti-inflammatory and antirheumatic products, nonsteroids
  1. M Musculo-skeletal system drugs
    1. M01 Antiinflammatory and antirheumatic products
      1. M01A Antiinflammatory and antirheumatic products, non-steroids
        1. M01AE Propionic acid derivatives, antiinflammatory and antirheumatic products
          1. M01AE02 naproxen
Marketing authorisation PL 44041/0199 (first authorised 23 November 2021)
Marketing authorisation holder NOUMED LIFE SCIENCES LIMITED

Sources: the MHRA product information (products.mhra.gov.uk). Contains public sector information licensed under the Open Government Licence v3.0.