Aspirin low dose

The SALT Collaborative Group Swedish Aspirin Low-dose Trial (SALIT of 75 mg aspirin as secondary prophylaxis after cerdvovascular ischaemic events. Lancet 338 1345,1991... 

SALT Colldyuative Group. Swedish aspirin low-dose trial (SALT) of 75mg aspirin as secondary... 

Aspirin has been remarkably successful in the treatment of the pain and swelling of inflammatory disease and in fact, an estimated 45,000 tons of aspirin are still consumed each year. This success resulted in the syntheses of many other aspirin-like drugs , now referred to as NSAIDs. Aspirin, however, continues to have a unique use in the prevention of thrombosis. Since it produces irreversible inhibition of COX-1 by acetylation of serine at position 530 in the active site, a daily low dose of aspirin will cause a cumulative inhibition of COX-1 in platelets, in the portal circulation. A gradual inhibition of platelet aggregation occurs, reducing the possibility of occlusion of coronary or cerebral vessels by platelet thrombi. However, there are no systemic... 

Acetylsalicylic acid irreversibly inhibits both COX-1 and COX-2 by acetylating the enzymes. Since mature platelets lack a nucleus, they are unable to synthesise new enzyme. The anti-platelet effects of acetylsalicylic acid persist therefore throughout the lifetime of the platelet and the half-life of this effect is thus being much longer than the elimination half-life of acetylsalicylic acid (15 min). Since new platelets are continuously launched into the circulation, the clinically relevant anti-platelet effect of aspirin lasts for up to five days. This is the reason why low doses of acetylsalicylic acid (ca. 100 mg per day) are sufficient in the prophylaxis of heart attacks. 

Jenkins C, Costello J, Hodge L Systematic review of prevalence of aspirin-induced asthma and its implications for clinical practice. BMJ 2004 328 434-437. Baldassarre S, Schandene L, Choufani G, Michils A Asthma attacks induced by low doses of celecoxib, aspirin and acetaminophen. J Allergy Clin Immunol 2006 117 215-217. 

This was largely influenced by the high-dose UFH group in 1ST (OR 1.38, 95% Cl 1.05-1.82). An interaction by UFH dose (p = 0.01) on recurrent stroke risk with combination UFH-aspirin therapy compared to aspirin monotherapy was observed, with a trend toward increased risk of recurrent stroke with high-dose UFH + aspirin (OR 1.22, 95% Cl 0.92-1.62) and a trend toward reduced risk with low-dose UFH + aspirin (OR 0.75, 95% Cl 0.56-1.03), equivalent to 10 fewer (95% Cl 0-20 fewer) recurrent strokes per 1000 patients treated. They found a small, but significant beneht of LMWH over aspirin in the prevention of symptomatic DVT, equivalent to 10 (95% Cl 0-30) fewer DVTs per 1000 patients treated. Compared with aspirin, anticoagulants were associated with nonsignificantly fewer symptomatic PEs (OR 0.85, 95% Cl 0.55-1.32). There were fewer PEs with the combination of UEH and aspirin (OR 0.58, 95% Cl 0.34—1.00), equivalent to 5 fewer (Cl 0-10) PEs per 1000 patients treated. However, the overall incidence of symptomatic DVT and PE was low (1.1% and 0.7%). 

Aspirin should be started within 48 hours of stroke onset and may be used safely in combination with low doses of subcutaneous heparin for DVT prophylaxis. 

Low-dose heparin should be restricted for 24 hours after administration of thrombolytic therapy. Low-dose heparin may be used safely in combination with aspirin. 

Administered to achieve an INR of 2.5 (range 2-3) in combination with low-dose aspirin pharmacotherapy (<100 mg daily [Chest guidelines] or 75-162 mg daily [Circulation guidelines]) for 3 mo postmyocardial infarction. Repeat echocardiogram before discontinuing warfarin pharmacotherapy... 

Other gastrointestinal disturbances, including dyspepsia and nausea, are infrequent when low-dose aspirin is used. Aspirin therapy should be continued indefinitely. 

Previous peptic ulcer disease or upper gastrointestinal bleeding Cardiovascular disease and other comorbid conditions Multiple NSAID use (e.g., low-dose aspirin in conjunction with another NSAID)... 

Cardiovascular Keep doses of NSAIDs and glucocorticoids low, consider initiation of folic acid to reduce homocysteine level elevations induced by methotrexate, consider initiation of low-dose aspirin and/or HMG-CoA reductase inhibitors (statins), and encourage smokers to discontinue tobacco use and assist with the development of a tobacco-cessation plan.11,12... 

Some drugs can cause hyperuricemia and gout, such as thiazide diuretics, niacin, pyrazinamide, cyclosporine, and occasionally, low-dose aspirin. 

Some drugs can cause hyperuricemia and gout, such as thiazide diuretics, niacin, pyrazinamide, cyclosporine, and occasionally, low-dose aspirin. In most cases, these drugs block uric acid secretion in the kidney. Long-term consequences of gout and hyperuricemia include joint destruction, tophi, and nephrolithiasis. 

Aspirin is maximally effective as an antithrombotic agent at the comparatively low dose of 81 to 325 mg per day. (The antipyretic dose of aspirin in adults is 325 to 650 mg every 4 h.) Higher doses of aspirin are actually contraindicated in patients prone to thromboembolism. At higher doses, aspirin also reduces synthesis of prostacyclin, another arachidonic acid metabolite. Prostacyclin normally inhibits platelet aggregation. The prophylactic administration of low-dose aspirin has been shown to increase survival following myocardial infarction, decrease incidence of stroke, and assist in maintenance of patency of coronary bypass grafts. 

The Patient on Low-Dose Aspirin For Neuraxial Anesthesia Part 1. McMahonMed.com, http //www.mcmahonmed.com/cme/an/cme176/05lesson.htm... 

Low-dose aspirin is associated with a reduced risk of major bleeding, particularly GI bleeding. Other GI disturbances (e.g., dyspepsia, nausea) are infrequent with low-dose aspirin. Ibuprofen should not be administered on a regular basis concurrently with aspirin because it may block aspirin s antiplatelet effects. 

Because of the potential increased risk for bleeding with combination antiplatelet therapy, a low dose of aspirin (75 to 100 mg/day) is recommended for maintenance therapy with clopidogrel. 

The risk of major bleeding from chronic aspirin therapy is approximately 2% and is dose related. Therefore, after an initial dose of 325 mg, chronic low doses of 75 to 81 mg are recommended unless a stent is placed. 

The AHA/ASA guidelines recommend that antiplatelet therapy as the cornerstone of antithrombotic therapy for the secondary prevention of ischemic stroke and should be used in noncardioembolic strokes. Aspirin, dopidogrel, and extended-release dipyridamole plus aspirin are all considered first-line antiplatelet agents (see Table 13-1). The combination of aspirin and clopido-grel can only be recommended in patients with ischemic stroke and a recent history of myocardial infarction or coronary stent placement and then only with ultra-low-dose aspirin to minimize bleeding risk. 

For women at high risk for preeclampsia, low-dose aspirin after 12 weeks gestation reduces the risk for preeclampsia by 19%. Aspirin may reduce the risk of preterm birth by 7% and fetal or neonatal death by 16%. Calcium, 1 g/day, is recommended for all pregnant women, as it may help prevent hypertension in pregnant women and reduce the risk of preeclampsia by 31% to 67%. 

Collaborative Group of the Primary Prevention Project (2001) Low-dose aspirin and vitamin E in people at cardiovascular risk a randomised trial in general practice. Lancet 357 89-95... 

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