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Terms Of Use


Brand Name(s) : Naprosyn, Naprosyn EC, Feminax Ultra
Side Effects


Naproxen should be used with caution in:


What is it used for?

  • Naproxen is used to reduce pain and inflammation.
  • It is a non-steroidal anti-inflammatory drug, sometimes known as an NSAID. Naproxen is also known as a COX inhibitor as it blocks the action of a chemical in the body called cyclo-oxygenase (COX).
  • It is used to relieve pain and inflammation in a wide variety of musculoskeletal conditions including various types of arthritis- a painful condition of the joints. Naproxen can also be used to relieve period pain.
  • In general this drug is used to treat osteoarthritis, rheumatoid arthritis (including in children), ankylosing spondylitis, attacks of gout and other musculoskeletal conditions such as joint pain, muscular pain and back pain as well as painful periods. Naproxen works by blocking the action of cyclo-oxygenase (COX), which is involved in the production of chemicals that cause pain, swelling and inflammation.
  • Benefits of being on this drug can include a reduction in the level of pain and inflammation leading to an improvement in the movement and mobility of people with conditions affecting muscles and joints. This also helps improve the general quality of life of people with these conditions.

Listed below are the typical uses of naproxen.

  • Rheumatoid arthritis (an inflammatory type of arthritis normally starting in the hands)
  • Osteoarthritis (a degenerative type of arthritis caused by wear and tear)
  • Juvenile rheumatoid arthritis
  • Ankylosing spondylitis (a type of arthritis affecting the spine)
  • Other musculoskeletal conditions such as joint pain, back pain, gout, muscle strains and tendonitis
  • Period pain (dysmenorrhoea)

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


Take this medication orally usually twice daily, with or after food. This medication should be swallowed whole.

Use this medication for duration of prescription in order to get the most benefit from it.

Remember to use it at the same time each day - unless specifically told otherwise by your doctor.

It may take up to a few weeks before the full benefit of this drug takes effect, but it can start to relieve pain after 1-2 days.

Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • This medication may cause tiredness, drowsiness or dizziness or other side effects which may affect your ability to drive or operate machinery. If you are affected you should avoid driving or operating machinery until you feel safe to do so. Consult your doctor or pharmacist for more details.

When can I stop?

  • This depends on the condition that you are being treated for. It is important to take naproxen for the shortest time necessary to control symptoms due to the risk of side effects. However, stopping treatment for long-term conditions may cause your original condition to return. Consult your doctor or pharmacist for more details.


If any of these persist or you consider them severe then inform doctor or pharmacist.

Stop taking medication and tell your doctor immediately if you develop any of the following symptoms:

  • Stomach and intestinal bleeding, seen in vomit as blood or looks like coffee grounds. It is very important to inform your doctor of this side effect as this an be life threatening.
  • Yellowing eyes or skin
  • Signs of hepatitis, including tiredness, appetite loss, nausea, vomiting, pale coloured stools (motions)
  • Problems/ changes in blood tests
  • Rectal bleeding, seen in faeces
  • Stomach or gut ulcers, signs include upset and painful stomach or gut
  • Mouth ulcers
  • Stomach and intestinal tears (perforation)
  • Severe diarrhoea
  • Severe rash, blistering or peeling of skin
  • Blistering of skin when exposed to sunlight
  • Chest pain, which may spread to neck, shoulders and left arm
  • Muscle weakness or numbness, which may only be down one side of the body
  • Altered sense of smell, taste, hearing or vision
  • Signs of meningitis, including stiff neck, headache, nausea, vomiting, fever, confusion and sensitivity to light

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking naproxen, tell your doctor or pharmacist if you are allergic to it; or to other NSAIDs; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: allergy to naproxen, or any of its ingredients, allergy to aspirin, other NSAIDs or other pain relief medications (such as ibuprofen), are a child under 16 years of age unless for juvenile rheumatoid arthritis, are in the last 3 months of pregnancy, are breastfeeding, active or history of stomach ulcers, tear (perforation) or bleeding, history of stomach ulcers, tear (perforation) or bleeding due to previous NSAIDs medication, severe kidney, liver or heart failure.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: reduced kidney or liver function, mild to moderate congestive heart failure, heart disease due to low blood flow to heart, such as angina, high blood pressure (hypertension), blood clotting (coagulation) disorders, systemic lupus erythematosus (SLE) or other connective tissue disorders, gastrointestinal disease, such as Crohn's disease and ulcerative colitis, asthma, or a history of, allergies, such as hayfever, rhinitis (runny nose), polyps (lumps in the nose), angio-oedema (swelling of face), high fat levels in blood, such as high cholesterol levels, diabetes mellitus, smoking, pregnancy, problems becoming pregnant.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol intake is not known to affect naproxen.

The elderly: naproxen should be used with caution in the elderly as it may increase the likelihood of side effects from using this medication, particularly gastrointestinal bleeding. It is recommended that this medication is not used as long term treatment for the elderly.

Pregnancy and breast-feeding - please ensure you read the detailed information below


Planning to become pregnant: Naproxen is not recommended in women trying to conceive as the medication may affect fertility.

First trimester: Naproxen should not be used during the first trimester of pregnancy (first 3 months) unless the potential benefit to the patient outweighs the potential risk to the unborn baby.

Second trimester: Naproxen should not be used during the second trimester of pregnancy (from 3-6 months) unless the potential benefit to the patient outweighs the potential risk to the unborn baby.

Third trimester: Naproxen is not safe to use in the third trimester (last 3 months) of pregnancy because it can harm the unborn baby.

Labour and delivery: Naproxen is not recommended during labour and delivery.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Naproxen is not safe to take if you are breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • None known.

If you are currently using any of these medications, tell your doctor or pharmacist before starting naproxen.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • Medicines used to prevent blood clotting, such as warfarin and heparin
  • Other painkillers (NSAIDs), such as ibuprofen, celecoxib and etoricoxib
  • Aspirin
  • Diuretic medication, such as furosemide
  • ACE inhibitors (to lower blood pressure)
  • Cardiac glycosides such as digoxin (used to treat heart failure)
  • Lithium
  • Antidepressants, such as fluoxetine and citalopram
  • Probenecid (used to treat gout)
  • Methotrexate (used to treat cancer, psoriasis and rheumatoid arthritis)
  • Ciclosporin (an immunosuppressant used to prevent transplant rejection, psoriasis and rheumatoid arthritis)
  • Corticosteroids (used to treat inflammatory conditions including asthma)
  • Quinilone antibiotics
  • Tacrolimus (used in eczema and to prevent transplant rejection)
  • Zidovudine (for HIV infections)
  • Hydantoins such as phenytoin (for epilepsy)
  • Mifepristone (used to terminate pregnancies)
  • Sulphonamide medication, including sulphonamide antibiotics
  • Sulphonylureas (for diabetes), such as glibenclamide

This information does not contain all possible interactions. Therefore, before using naproxen, tell your doctor or pharmacist of all the products you use.


Symptoms of overdose include headache, heartburn, nausea, vomiting, stomach pain, gastrointestinal bleeding, disorientation, excited state, drowsiness, dizziness, ringing in the ears, fainting and diarrhoea.

In cases of significant poisoning acute renal (kidney) failure and liver damage are possible. Respiratory depression with severe breathing problems and coma may occur after the ingestion of NSAIDs but are rare.

Patients should be treated symptomatically as required.

If you take more than you should, talk to your doctor or go to hospital straight away. Take the medicine pack with you.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of naproxen or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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