Naprosyn EC tablets contain the active ingredient naproxen, which is a type of medicine called a non-steroidal anti-inflammatory drug (NSAID). NSAIDs are used to relieve pain and inflammation. (NB. Naproxen is also available without a brand name, ie as the generic medicine.)
Naproxen works by blocking the action of a substance in the body called cyclo-oxygenase (COX). Cyclo-oxygenase is involved in the production of various chemicals in the body, some of which are known as prostaglandins. Prostaglandins are produced by the body in response to injury and certain diseases and conditions, and cause pain, swelling and inflammation. Naproxen blocks the production of these prostaglandins and is therefore effective at reducing inflammation and pain.
Naproxen is used to relieve pain and inflammation in a wide range of musculoskeletal conditions, including various forms of arthritis, gout, muscle sprains and strains, back pain, neck pain and tendinitis. It can also be used to relieve period pain.
Naprosyn EC tablets have a special 'enteric coat' that is designed to prevent the tablet breaking down and releasing the naproxen in the stomach, and thus reduce the risk of it irritating the stomach. When the tablet reaches the intestine, the coating dissolves and the naproxen is absorbed into the bloodstream. The tablets should be swallowed whole and not broken or chewed to avoid damaging this coating.
This medicine may cause dizziness or drowsiness and so may affect your ability to drive or operate machinery safely. Do not drive or operate machinery until you know how this medicine affects you and you are sure it won't affect your performance.
- Very rarely, NSAIDS may cause serious blistering or peeling skin reactions (eg Stevens-Johnson syndrome, toxic epidermal necrolysis, exfoliative dermatitis). For this reason, you should stop taking this medicine and consult your doctor if you get a skin rash or sores inside your mouth while taking this medicine. This side effect is very rare, but if it occurs, is most likely to happen in the first month of treatment.
- If you have cirrhosis of the liver, heart failure or kidney disease, you are on a low sodium diet, or you are taking diuretic medicines, your kidney function should be assessed before starting and regularly throughout treatment with this medicine.
- During long-term treatment with this medicine you should have regular check-ups with your doctor so that you can be monitored for possible side effects of the medicine. This might include routine blood tests to monitor your kidney function, liver function and levels of blood components, particularly if you are elderly.
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before taking this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.
Indigestion remedies such as antacids should not be taken at the same time of day as enteric-coated naproxen tablets, as they will stop the special coating from working.
Naproxen should not be taken in combination with painkilling doses of aspirin or any other NSAID taken by mouth, eg ibuprofen, as this increases the risk of side effects on the stomach and intestines. Selective inhibitors of COX-2 such as celecoxib or etoricoxib should also be avoided for the same reason.
