Even though aspirin (ASA-acetyl salicylic acid) was developed by the Bayer Company in 1897, its mode of action was not known until 1971 when a pharmacologist in England discovered the chemical entity now known as prostaglandin (PG). The inhibition or blocking of this chemical is the mechanism of action of ASA and the NSAIDs, (non-sterioidal anti-inflammatories)specifically by interfering with the enzyme (chemical “sparkplug”) cyclooxygenase (COX). Twenty years later further research led to the discovery of 2 forms of COX, one which controlled maintaining a healthy stomach lining, kidneys, blood flow, and platelet function (COX-1) and another which served to induce pain and inflammation when tissue damage was present. (COX-2).
The establishment of the COX 1 and 2 led researchers to develop those compounds/drugs to block specifically the COX-2 receptors, thus blocking the inflammatory and pain without blocking the beneficial aspects of COX-1. Though 3 compounds were developed and were beneficial, only the initial drug- Celebrex is still available. Due to alleged cardiac and other organ side effects both Vioxx and Bextra were withdrawn by the manufacturers. By 2000, the COX-2 drugs ranked 8th in all sales of prescriptions.
Celebrex (Celecoxib) is FDA (Federal Drug Administration) approved for RA (rheumatoid arthritis) and OA (osteoarthritis also known as DJD degenerative joint disease). Dosed at 100-200mg twice daily it is effective as naproxen 500 twice daily or diclofenac 75mg twice daily for the relief of RA symptoms-joint pain, swelling, stiffness.
As a COX-2 it still may cause abdominal pain (4%) and diarrhea (6%); however studies do confirm less gastric (stomach) or duodenal (intestinal) ulcerations then the NSAIDs. Celebrex is used in patients on blood thinners or with blood diseases since it doesn’t interfere with platelets as the NSAIDs.
Celebrex should NOT be given to patients with allergies to sulfa drugs, aspirin, NSAIDs, or with aspirin-sensitive asthma, kidney disease, pregnant women or those with heart failure and or fluid retention. It may lower certain blood pressure (Beta blockers) medication effects, may increase lithium levels, and may increase the blood concentrations of methotrexate (a RA drug) or fluconazole (antifungal drug). These drug interactions are due to the mode of drug metabolism (breakdown and clearance from the body) in the liver by cytochrome p-450 system as these other drugs share a similar mode, however the isoenzyme differs. Despite its selectivity, gastric upset is possible along with peripheral (extremity) edema, pharyngitis and may cause elevated liver enzymes.
Skin reactions may include Stevens-Johnson syndrome (a red rash like skin appearance ‘”Red Man’s disease”)exfoliative dermatitis (a peeling of the skin as in sunburn)
Celebrex is available as 100, 200, and 400mg capsules. The drug should be dosed at the lowest possible dosage on an individual basis, to achieve the desired result for the diagnosed problem.
For osteoarthritis, the usual oral daily dose in 200mg daily given in 100mg capsules dosed twice daily. For relief of rheumatoid arthritis the usual does is 100 -200mg twice daily. For the treatment of dysmenorrheal(painful menses) , Celebrex is recommended with an initial dose of 400mg to start, then a second dose of 200mg later the same day, followed by 200mg twice daily as needed. Cox-2 PG(prostaglandin) is believed to play a prominent role in cancer cell proliferation in certain growths such as familial adenomatous polyposis(FAP),and interferes with the immune response to cancerous cells, by rendering natural cancer-killing cells ineffective, Celebrex is recommended in doses of 400mg twice daily with food for this disease.
I have found Celebrex effective especially in acute gouty arthritis patients on coumadin or with a history of stomach sensitivity or ulcers. Post-operatively it is an effective analgesic (relieves pain) of value because it doesn’t affect platelets. Celebrex is generally well tolerated which stimulates compliance in patients' treatment of inflammation due to injury or acute flare up of arthritic conditions. Celebrex is not used in children, and since it is the only COX-2 inhibitor available, is a good medication when used appropriately for the proper patient population.
See our other pain medication discussions.