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Non-Steroidal Anti-Inflammatory Drugs Comparison
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly prescribed categories of drugs worldwide in the treatment of pain and inflammation in many conditions. Nonsteroidal anti-inflammatory drugs have anti-inflammatory, analgesic, and antipyretic effects and inhibit thrombocyte aggregation. NSAIDs are used primarily to treat inflammation, mild-to-moderate pain, and fever. Specific uses include the treatment of headaches, arthritis, sports injuries, and menstrual cramps. Aspirin is used to inhibit the clotting of blood and prevent strokes and heart attacks in individuals at high risk. NSAIDs also are included in many cold and allergy preparations. NSAIDs do not cure the diseases or injuries. Two drugs in this category, ibuprofen and naproxen, also reduce fever. NSAIDs block the Cox enzymes and reduce prostaglandins throughout the body. As a consequence, ongoing inflammation, pain, and fever are reduced. Since the prostaglandins that protect the stomach and support the platelets and blood clotting also are reduced, NSAIDs can cause ulcers in the stomach and promote bleeding. (NSAIDs do not cause bleeding, but they make bleeding worse, for example, when there is a cut.) NSAIDs differ in how strongly they inhibit Cox-1 and, therefore, in their tendency to cause ulcers and promote bleeding. NSAIDs are usually indicated for the treatment of acute or chronic conditions where pain and inflammation are present. Nonsteroidal anti-inflammatory drugs are powerful analgesics, especially for nociceptive pain. NSAIDs also are effective in some neuropathic pain syndromes when used with other analgesics. NSAIDs are generally indicated for the symptomatic relief of the following conditions:
There are many different types of NSAIDs:
Acetaminophen, ibuprofen, naproxen, and ketoprofen are available as over-the-counter drugs in the United States. NSAIDs work by suppressing the production of fatty acids called prostaglandins that cause inflammation and pain. They do this by blocking the action of an enzyme, cyclooxygenase (COX). This enzyme is responsible for converting precursor acids into prostaglandins. In the periphery NSAIDs work by decreasing the sensitivity of the nociceptor to painful stimuli induced by heat, trauma, or inflammation. In the central nervous system, they are thought to function as antihyperalgesics and block the increased transmission of repetitive incoming signals to higher centers. In effect, they modulate perception of pain caused by repetitive stimulation from the periphery. Since they function by modulation of the perception of pain, they may be useful when given in the preoperative period and may reduce the need for postoperative analgesia. NSAIDs vary in their potency, duration of action, and the way in which they are eliminated from the body. Another important difference is their ability to cause ulcers and promote bleeding. The more an NSAID blocks Cox-1, the greater is its tendency to cause ulcers and promote bleeding. Aspirin is a unique NSAID, not only because of its many uses, but because it is the only NSAID that is able to inhibit the clotting of blood for a prolonged period (4 to 7 days). This prolonged effect of aspirin makes it an ideal drug for preventing the blood clots that cause heart attacks and strokes. Most other NSAIDs inhibit the clotting of blood for only a few hours. The major NSAIDs of potency comparable to opioids are diclofenac and ketorolac. Moderate postoperative pain, for example, may be managed using these agents. Ketorolac (Torodol) is a very potent NSAID and is used for moderately severe pain that usually requires narcotics. The overall analgesic effect of 30 mg of ketorolac is equivalent to that of 6 to 12 mg of morphine. Efficacy has been demonstrated for postsurgical pain including oral, orthopedic, gynecologic, and abdominal procedures. Efficacy for acute musculoskeletal pain has also been shown. Its antipyretic activity is significant. Anti-inflammatory activity is achieved only at doses higher than those needed for analgesia. Ketorolac causes ulcers more frequently than any other NSAID and is, therefore, not used for more than five days. The selection of a specific formulation of diclofenac is important because only one of the available formulations (sodium or potassium salts ) of diclofenac provides prompt relief (potassium formulation), a characteristic essential in the management of acute pain. Efficacy has been demonstrated with postoperative pain including gynecologic, oral, and orthopedic surgery models, as well as dysmenorrhea. Naproxen provides effective relief in acute traumatic injury and for acute pain associated with migraine, tension headache, postoperative pain, postpartum pain, pain consequent to various gynecologic procedures, and the pain of dysmenorrhea. Choice of NSAID for chronic and disabling inflammatory joint diseases like rheumatoid arthritis and osteoarthritis is governed by age, diagnosis, degree of severity, relative gastrointestinal safety, tolerability, and relative efficacy in the given clinical situation. It is a common misconception that all NSAIDs are therapeutically equally efficacious and any one of them could be used for the given indication. Use of multiple NSAIDs should be discouraged. An agent with comparatively less gastrointestinal (GI) side effects like ibuprofen and diclofenac should be preferred in place of indomethacin, piroxicam, or naproxen, which are more gastrotoxic. In conditions where inflammation of joints is minimal (e.g. osteoarthritis) analgesics, like paracetamol should be preferred over anti-inflammatory drugs like ibuprofen. In conditions where diagnosis is uncertain, the medicine should be empirically chosen and given for a week or so and if the response is adequate it should be continued until side effects mandate its withdrawal. Ankylosing spondylitis responds better to a particular NSAID like indomethacin. It is probably related to its stronger inhibition of prostaglandin synthesis. The analgesic effect of 10 anti-inflammatory drugs was compared using a single-blind method in 90 patients with rheumatoid arthritis. Each patient received two different drugs, for three days each and each drug was evaluated in 18 patients. After the trial, the patients considered which of the drugs they preferred. The greatest relief from pain was achieved by diclofenac, indomethacin, naproxen and tolfenamic acid, each of these being preferred by the majority of patients and being significantly (p>0.01) better than the least effective drugs ketoprofen and proquazone. Acetylsalicylic acid, azapropazone, carprofen and ibuprofen were considered intermediate in efficacy. NSAIDs are associated with a number of side effects. The two main adverse drug reactions, associated with NSAIDs relate to gastrointestinal effects and renal effects of the agents. These effects are dose-dependent, and in many cases severe enough to pose the risk of ulcer perforation, upper gastrointestinal bleeding, and death, limiting the use of NSAID therapy.
Use of aspirin in children and teenagers with chicken pox or influenza has been associated with the development of Reyes's syndrome. Therefore, aspirin and nonaspirin salicylates (e.g. salsalate) should not be used in children and teenagers with suspected or confirmed chicken pox or influenza. The frequency of side effects varies between the drugs. There are also some differences in the propensity of individual agents to cause gastrointestinal adverse drug reactions (ADRs). Indomethacin, ketoprofen and piroxicam appear to have the highest prevalence of gastric ADRs, while ibuprofen (lower doses) and diclofenac appear to have lower rates. A meta-analysis of 11 case-control studies and one cohort study found that ibuprofen was significantly less toxic than other NSAID. Serious side effects are especially likely with one nonsteroidal anti-inflammatory drug, phenylbutazone. Patients of age 40 and over are especially at risk of side effects from this drug, and the likelihood of serious side effects increases with age. Because of these potential problems, it is especially important to check with a physician before taking this medicine. Never take it for anything other than the condition for which it was prescribed, and never share it with another person. Precautions & Contraindications NSAIDs cannot be used (are contraindicated) in the following cases:
Numerous NSAIDs are available as generics and include: diclofenac, etodolac, fenoprofen, flurbiprofen, ibuprofen, indomethacin, ketoprofen, meclofenamate, naproxen, piroxicam, sulindac, and tolmetin. Only meloxicam (brand name: Mobic), nabumetone (brand name: Relafen), and oxaprozin (brand name: Daypro) are available by brand name only. Generic medications may be an equally effective and less expensive treatment option. Drug prices:
All NSAIDs are similarly effective. The choice of which NSAID to try first is usually empiric. If one doesn't provide adequate pain control, try switching to another. All NSAIDS when used chronically can be associated with the development of ulcers. Differences in adverse effects seem to exist between different NSAIDs. Follow with your doctor closely and watch for signs or symptoms of gastrointestinal bleeding such as stomach pain and blood in the stools. Some NSAIDs are available in extended-release formulations that require less frequent dosing. |
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