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1. NSAIDs 有flat dose response，一般使用不建議超過最大劑量。
2. 一般在給NSAIDs時，可考慮以低劑量多頻次來改善病患的疼痛，例如：ibuprofen 400mg q4h和ibuprofen 600mg q6h擁有相同的止痛效果，但是ibuprofen 400mg組有較低的side effects發生率。

Aspirin is a unique NSAID 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.

NSAIDs裏唯一抑制血小板（不可逆）長達4-7天，其餘僅幾個小時。

Celecoxib has a sulfonamide structure and is contraindicated for patients with known sulfa allergy.

結構有磺胺，G6DP缺乏及對結構過敏者禁用

Diclofenac is relatively long acting (6 to 8 hours) but it has a relatively very short half-life. Diclofenac is also a unique member of the NSAIDs. There is some evidence that diclofenac inhibits the lipoxygenase pathways, thus reducing formation of the leukotrienes (also pro-inflammatory autacoids). There is also speculation that diclofenac may inhibit phospholipase A2. These additional actions may explain the high potency of diclofenac - it is one the most potent NSAIDs.

As an analgesic, diclofenac is 6 times more potent than indomethacin and 40 times as potent as aspirin in the phenyl benzoquinone-induced writhing assay in mice.

Diclofenac use increases the risk of heart attack and stroke.

Diclofenac 止痛效果是indomethacin得6倍，asspirin得40倍。有中風風險。

Etodolac, with regard to its anti-inflammatoryproperties, is approximately 50 times more active than aspirin, three times more potent than sulindac, and one-third as active as indomethacin. Although etodolac is no more potent than many other NSAIDs, a low incidence of GI side effects is an important therapeutic advantage.

消炎效果是aspirin得50倍，sulindac的3倍，indomethacin的1/3倍。GI風險小是他的好處。

Fenoprofen has less potent in anti-inflammatory action than ibuprofen, indomethacin, ketoprofen, or naproxen.

Flurbiprofen was found to be 536-fold more potent than aspirin and 100-fold more potent than phenylbutazone. Oral flurbiprofen is half as potent as methylprednisolone. Flurbiprofen is 26 times more potent than ibuprofen as an antinociceptive.

止痛效果是ibuprofen的26倍。

Ibuprofen has the lowest risk of causing GI bleeding.

有最小的腸胃道副作用。劑量小於2400mg/day不具消炎效果。

Indomethacin, a very potent COX inhibitor, besides its high cardiovascular risk, has a significant GI toxicity and many central nervous system side effects. Indomethacin should not be used by children <14 years and during pregnancy.

Indomethacin is still one of the most potent NSAIDs in use. It is also a more potent antipyretic than either aspirin or acetaminophen, and it has about 10 times the analgesic potency of aspirin. However, its beneficial analgesic effect is definitely overshadowed by pronounced side effects.

有高的CV, GI和CNS風險。解熱效果比panadol和aspirin好，止痛效果是aspirin的十倍。可能導致血小板缺乏及高血鉀症。

Ketoprofen, unlike many NSAIDs, inhibits the synthesis of leukotrienes and leukocyte migration into inflamed joints in addition to inhibiting the biosynthesis of prostaglandins. Ketoprofen stabilizes the lysosomal membrane during inflammation, resulting in decreased tissue destruction. Although it is less potent than indomethacin, its gastrotoxicity is about the same. Ketoprofen may cause photosensitivity.

 半衰期約1-3hr，完全由肝代謝，可用在關節炎、痛風、經痛，效果並未優於其他NSAIDs。

Ketorolac is the most potent and most effective NSAID analgesic, with efficacy comparable to opioids4. The analgesic effect of 30 mg of ketorolac is similar to 10 mg of morphine. Anti-inflammatory activity is achieved only at doses higher than those needed for analgesia. Ketorolac has the highest incidence of side effects, and is, therefore, not used for more than five days.

止痛效果好，30mg的ketorolac（一支keto inj）＝10mg morphine止痛效果。因副作用大，不能使用超過五天。多用於全身性之止痛作用。

Meloxicam was initially introduced as a selective COX-2 inhibitor. However, it is less selective for COX-2 than is celecoxib. Meloxicam causes fewer GI complications than piroxicam.

 比piroxicam有較少的腸胃副作用。一般劑量為7.5mg qd。劑量越大gi副作用越大。

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. Naproxen has a lowest risk of provoking heart attack. It may cause photosensitivity.

 CV Risk最小。多用在止痛。

Piroxicam has a long plasma half-life (38 hours), which permits a single daily dosing. Piroxicam is indicated for long-term use in rheumatoid arthritis and osteoarthritis. Its gastrotoxicity is relatively high.

Sulindac, an analog of indomethacin, is unique among the NSAIDs in not inhibiting prostaglandin synthesis in the kidneys . So, it may be one of the safest drugs for treating osteoarthrosis in older people. Sulindac may cause increased liver enzymes.

腎毒性最小，有利於年長者的使用。可能導致肝臟酵素上升及血小板缺乏。

＊短半衰期的NSAIDs存在關節液中的時間較長半衰期所預期的長。Diclofenac可存在關結液中2-6hr。 

*diclofenac K+比Na+吸收快，鉀鹽（cataflam）故onset較納鹽（voltaren）快

*止痛：ketorolac>mobic>diclofenac=ketoprofen>celebrex>flurbiprofen>ibuprofen>naproxen>aspirin=panadol

*消炎：indomethacin>etodolac>sulindac>fenoprofen

僅供參考，敬請指教，謝謝

reference: http://www.emedexpert.com/compare/nsaids.shtml, Basic and clincal pharmacology