Aspirin Dosage

Medically reviewed by Drugs.com. Last updated on Aug 14, 2023.

Usual Adult Dose for Osteoarthritis

Initial dose: 3 g orally per day in divided doses
Maintenance: Adjust dose as needed for anti-inflammatory efficacy

Comments:

• Dosing should be individualized.
• Target plasma salicylate levels of 150 to 300 mcg/mL are associated with anti-inflammatory response while plasma salicylate levels greater than 200 mcg/mL are associated with a higher incidence of toxicity.

Uses: For the relief of the signs and symptoms of rheumatoid arthritis, osteoarthritis, and arthritis and pleurisy associated with systemic lupus erythematous.

Usual Adult Dose for Rheumatoid Arthritis

Initial dose: 3 g orally per day in divided doses
Maintenance: Adjust dose as needed for anti-inflammatory efficacy

Comments:

• Dosing should be individualized.
• Target plasma salicylate levels of 150 to 300 mcg/mL are associated with anti-inflammatory response while plasma salicylate levels greater than 200 mcg/mL are associated with a higher incidence of toxicity.

Uses: For the relief of the signs and symptoms of rheumatoid arthritis, osteoarthritis, and arthritis and pleurisy associated with systemic lupus erythematous.

Usual Adult Dose for Systemic Lupus Erythematosus

Initial dose: 3 g orally per day in divided doses
Maintenance: Adjust dose as needed for anti-inflammatory efficacy

Comments:

• Dosing should be individualized.
• Target plasma salicylate levels of 150 to 300 mcg/mL are associated with anti-inflammatory response while plasma salicylate levels greater than 200 mcg/mL are associated with a higher incidence of toxicity.

Uses: For the relief of the signs and symptoms of rheumatoid arthritis, osteoarthritis, and arthritis and pleurisy associated with systemic lupus erythematous.

Usual Adult Dose for Fever

Oral:
300 to 650 mg orally every 4 to 6 hours as needed
Maximum dose: 4 g in 24 hours

Rectal:
300 to 600 mg rectally every 4 hours

Uses: As a temporary fever reducer or for the temporary relief of minor pain due to headache, menstrual pain, arthritis, muscle pain, or toothache.

Usual Adult Dose for Pain

Oral:
300 to 650 mg orally every 4 to 6 hours as needed
Maximum dose: 4 g in 24 hours

Rectal:
300 to 600 mg rectally every 4 hours

Uses: As a temporary fever reducer or for the temporary relief of minor pain due to headache, menstrual pain, arthritis, muscle pain, or toothache.

Usual Adult Dose for Myocardial Infarction

Immediate-Release:
Initial dose: 160 to 162.5 mg orally once as soon as myocardial infarction is suspected
Maintenance dose: 160 to 162.5 mg orally once a day for 30 days post-infarction

Comments:

• Extended-release products should not be used when a rapid onset of action is desired such as suspected MI; non-enteric tablet may be chewed or crushed for immediate-action.
• This drug has been shown to reduce the risk of vascular mortality in patients with a suspected acute MI.
• After 30 days, secondary prophylaxis for prevention of recurrent MI should be considered.

Use: For treatment of a suspected myocardial infarction.

Usual Adult Dose for Ischemic Stroke

Immediate-release: 50 to 325 mg orally once a day

Extended-release (ER): 162.5 mg orally once a day

Comments:

• Therapy should be continued indefinately.
• ER capsules are designed to slowly release drug from encapsulated microparticles thereby prolonging the absorption across the gastrointestinal tract; the pharmacodynamic effect of ER 162.5 mg is similar to that attained with IR aspirin 81 mg..

Uses: To reduce the risk of death and recurrent stroke in patients who have had ischemic stroke or transient ischemia attack.

Usual Adult Dose for Ischemic Stroke - Prophylaxis

Immediate-release: 50 to 325 mg orally once a day

Extended-release (ER): 162.5 mg orally once a day

Comments:

• Therapy should be continued indefinately.
• ER capsules are designed to slowly release drug from encapsulated microparticles thereby prolonging the absorption across the gastrointestinal tract; the pharmacodynamic effect of ER 162.5 mg is similar to that attained with IR aspirin 81 mg..

Uses: To reduce the risk of death and recurrent stroke in patients who have had ischemic stroke or transient ischemia attack.

Usual Adult Dose for Angina Pectoris Prophylaxis

Immediate-release (IR): 75 mg to 325 mg orally once a day

Extended-release (ER): 162 mg orally once a day

Comments:

• Therapy should be continued indefinitely .
• The optimal dose to prevent cardiovascular events is unknown; however, higher doses are associated with increased risk of bleeding.
• Current evidence supports use of low-dose IR aspirin 75 to 100 mg daily.
• ER capsules are designed to slowly release drug from encapsulated microparticles thereby prolonging the absorption across the gastrointestinal tract; the pharmacodynamic effect of ER 162.5 mg is similar to that attained with IR aspirin 81 mg.

Uses: To reduce the combined risk of death and nonfatal myocardial infarction (MI) in patients with unstable angina pectoris and reduce the combined risk of MI and sudden death in patients with chronic stable angina pectoris.

Usual Adult Dose for Angina Pectoris

Immediate-release (IR): 75 mg to 325 mg orally once a day

Extended-release (ER): 162 mg orally once a day

Comments:

• Therapy should be continued indefinitely .
• The optimal dose to prevent cardiovascular events is unknown; however, higher doses are associated with increased risk of bleeding.
• Current evidence supports use of low-dose IR aspirin 75 to 100 mg daily.
• ER capsules are designed to slowly release drug from encapsulated microparticles thereby prolonging the absorption across the gastrointestinal tract; the pharmacodynamic effect of ER 162.5 mg is similar to that attained with IR aspirin 81 mg.

Uses: To reduce the combined risk of death and nonfatal myocardial infarction (MI) in patients with unstable angina pectoris and reduce the combined risk of MI and sudden death in patients with chronic stable angina pectoris.

Usual Adult Dose for Revascularization Procedures - Prophylaxis

For coronary artery bypass graft (CABG):
325 mg orally once a day beginning 6 hours after the procedure and continuing for 1 year

For percutaneous transluminal coronary angiography (PTCA):
325 mg orally once 2 hours prior to procedure, then 160 to 325 mg orally once a day indefinitely

For carotid endarterectomy:
80 mg orally once a day up to 650 mg orally twice a day beginning prior to surgery and continuing indefinitely

Comments:

• Current guidelines should be consulted for use of dual antiplatelet therapy (low-dose aspirin plus ticagrelor, clopidogrel, or prasugrel)

Uses: For patients who have undergone revascularization procedures including CABG, PTCA, or carotid endarterectomy when there is a preexisting condition for which aspirin is already indicated.

Usual Adult Dose for Ankylosing Spondylitis

Up to 4 g orally per day in divided doses
Maintenance dose: Adjust dose as needed for anti-inflammatory efficacy

Comments:

• Doses should be individualized.
• Target plasma salicylate levels of 150 to 300 mcg/mL are associated with anti-inflammatory response while plasma salicylate levels greater than 200 mcg/mL are associated with a higher incidence of toxicity.

Uses: For the relief of the signs and symptoms of spondyloarthropathies.

Usual Adult Dose for Myocardial Infarction - Prophylaxis

Primary Prophylaxis:

• 50 years or older: 75 to 100 mg orally once a day
• Adults with type 1 or type 2 diabetes at increased CVD risk: 75 to 162 mg orally once a day

Comments:

• In adults 50 to 59 years who have a 10% or greater 10-year CVD risk, are not at increased risk of bleeding, and have a life expectancy of at least 10 years, the United States Preventative Services Task Force (USPSTF) recommends initiating low dose aspirin for the primary prevention of atherosclerotic cardiovascular disease (ASCVD) and colorectal cancer (CRC).
• The decision to initiate primary prophylaxis therapy in adults 60 to 69 years, should include the same parameters and additionally be individualized for risk; for adults 70 years or older, the current evidence is insufficient to assess the balance of benefits and harms.
• The American Diabetes Association Standards of Care recommends primary prophylaxis in adults with diabetes who are at increased risk of CVD; this includes most patients 50 years or older with at least 1 additional major risk factor; for patients less than 50 years, clinical judgement is required.

Secondary Prophylaxis:
Immediate-release (IR): 75 mg to 325 mg orally once a day
Extended-release (ER): 162.5 orally once a day

Comments:

• The optimal dose to prevent cardiovascular events is unknown; however, higher doses are associated with increased risk of bleeding.
• Current evidence supports use of low-dose IR aspirin 75 to 100 mg daily.
• ER capsules are designed to slowly release drug from encapsulated microparticles thereby prolonging the absorption across the gastrointestinal tract; the pharmacodynamic effect of ER 162.5 mg is similar to that attained with IR aspirin 81 mg.

Use: To reduce the combined risk of death and nonfatal myocardial infarction (MI) in patients with chronic coronary artery disease, such as patients with a previous MI.

Usual Adult Dose for Cardiovascular Risk Reduction

Primary Prophylaxis:

• 50 years or older: 75 to 100 mg orally once a day
• Adults with type 1 or type 2 diabetes at increased CVD risk: 75 to 162 mg orally once a day

Comments:

• In adults 50 to 59 years who have a 10% or greater 10-year CVD risk, are not at increased risk of bleeding, and have a life expectancy of at least 10 years, the United States Preventative Services Task Force (USPSTF) recommends initiating low dose aspirin for the primary prevention of atherosclerotic cardiovascular disease (ASCVD) and colorectal cancer (CRC).
• The decision to initiate primary prophylaxis therapy in adults 60 to 69 years, should include the same parameters and additionally be individualized for risk; for adults 70 years or older, the current evidence is insufficient to assess the balance of benefits and harms.
• The American Diabetes Association Standards of Care recommends primary prophylaxis in adults with diabetes who are at increased risk of CVD; this includes most patients 50 years or older with at least 1 additional major risk factor; for patients less than 50 years, clinical judgement is required.

Secondary Prophylaxis:
Immediate-release (IR): 75 mg to 325 mg orally once a day
Extended-release (ER): 162.5 orally once a day

Comments:

• The optimal dose to prevent cardiovascular events is unknown; however, higher doses are associated with increased risk of bleeding.
• Current evidence supports use of low-dose IR aspirin 75 to 100 mg daily.
• ER capsules are designed to slowly release drug from encapsulated microparticles thereby prolonging the absorption across the gastrointestinal tract; the pharmacodynamic effect of ER 162.5 mg is similar to that attained with IR aspirin 81 mg.

Use: To reduce the combined risk of death and nonfatal myocardial infarction (MI) in patients with chronic coronary artery disease, such as patients with a previous MI.

Usual Adult Dose for Colorectal Cancer

50 years or older: 75 to 100 mg orally once a day

Comments:

• In adults 50 to 59 years who have a 10% or greater 10-year CVD risk, are not at increased risk of bleeding, and have a life expectancy of at least 10 years, the United States Preventative Services Task Force (USPSTF) recommends initiating low dose aspirin for the primary prevention of atherosclerotic cardiovascular disease (ASCVD) and colorectal cancer (CRC).
• The decision to initiate primary prophylaxis therapy in adults 60 to 69 years, should include the same parameters and additionally be individualized for risk; for adults 70 years or older, the current evidence is insufficient to assess the balance of benefits and harms.

Use: For the primary prevention of colorectal cancer.

Usual Pediatric Dose for Fever

12 years or older: 300 to 650 mg orally every 4 to 6 hours as needed
Maximum dose: 4 g in 24 hours

Comments:

• This drug should be avoided in pediatric patients with viral illness due to risk of Reye's syndrome.

Uses: As a temporary fever reducer or for the temporary relief of minor pain due to headache, menstrual pain, arthritis, muscle pain, or toothache.

Usual Pediatric Dose for Pain

12 years or older: 300 to 650 mg orally every 4 to 6 hours as needed
Maximum dose: 4 g in 24 hours

Comments:

• This drug should be avoided in pediatric patients with viral illness due to risk of Reye's syndrome.

Uses: As a temporary fever reducer or for the temporary relief of minor pain due to headache, menstrual pain, arthritis, muscle pain, or toothache.

Usual Pediatric Dose for Juvenile Rheumatoid Arthritis

Initial dose: 90 to 130 mg/kg orally in divided doses
Maintenance dose: Increase as needed for anti-inflammatory efficacy.

Comments:

• Dosing should be individualized.
• Target plasma salicylate levels of 150 to 300 mcg/mL are associated with anti-inflammatory response while plasma salicylate levels greater than 200 mcg/mL are associated with a higher incidence of toxicity.

Uses: For the relief of the signs and symptoms of juvenile rheumatoid arthritis.

Usual Pediatric Dose for Kawasaki Disease

Initial (acute phase): 80 to 100 mg/kg orally in divided doses for up to 14 days (as an anti-inflammatory agent)
Followed by: 1 to 5 mg/kg orally per day for 6 to 8 weeks (as an antiplatelet agent)

Comments:

• Intravenous Immune Globulin is recommended within 10 days of symptom onset.
• For children with moderate or giant coronary aneurysms following Kawasaki disease, warfarin may be needed in addition to low-dose aspirin; consult guidelines.
• For children who have giant aneurysms and acute coronary artery thrombosis, thrombolysis or acute surgical intervention is recommended.

Use: For the treatment of Kawasaki disease.

Usual Pediatric Dose for Thrombotic/Thromboembolic Disorder

1 to 5 mg/kg orally per day

Comments:

• The American College of Chest Physicians provides guidance on use of aspirin as antithrombotic therapy in neonates and children; their evidence based guidelines should be consulted for further guidance.
• May be used in neonates with recurrent Arterial Ischemic Stroke (AIS).
• For children with acute AIS, with or without thrombophilia, aspirin may be considered as initial therapy until dissection and embolic causes have been excluded; once dissection and cardioembolic causes are excluded, daily aspirin prophylaxis should continue for a minimum of 2 years.
• May be used for thromboprophylaxis in neonates and children after Modified Blalock-Taussig Shunts (MBTS) surgery; may be used in children after Fontan surgery
• For children with Ventricular Assist Devices (VADs) antiplatelet therapy (either aspirin or aspirin and dipyridamole) should begin within 72 hours of VAD placement.
• For children with acute AIS secondary to non-Moyamoya vasculopathy, aspirin may be considered as one option for initial therapy (for 3 months); ongoing antithrombotic therapy should be guided by repeat cerebrovascular imaging.
• For children with acute AIS secondary to Moyamoya, aspirin therapy should be considered; children should be referred to an appropriate center for consideration of revascularization.

Use: For antithrombotic therapy and prevention of thrombosis in neonates and children.

Renal Dose Adjustments

CrCl less than 10 mL/min: Contraindicated
CrCl 10 mL/min or greater: Use with caution

Liver Dose Adjustments

Severe hepatic impairment: Contraindicated
Mild to Moderate hepatic impairment: Use with caution

Precautions

Safety and efficacy of extended-release capsules have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Hemodialysis:

• Salicylate is removed and hemodialysis has been used to treat overdoses
• Consider administration after hemodialysis; monitor closely for bleeding

Peritoneal dialysis: May reduce aspirin concentrations

Other Comments

Administration advice:

• Take with a full glass of water, unless fluid restricted
• May take with or after meals to reduce gastrointestinal intolerance

Extended-release capsule:

• Take at approximately the same time every day
• Swallow capsules whole; do not cut, crush or chew
• Do not take 2 hours before or 1 hour after consuming alcohol

Enteric coated:

• Do not crush or chew

Suppository:

• Remove from plastic packet and insert into rectum as far as possible

Storage:
Suppository: Store in cool place (46F to 59F [8C to 15C]) or refrigerate

General:

• Dose-related adverse events may be minimized by prescribing the lowest effective dose.
• When aspirin is used in high doses, tinnitus has been used as a clinical signal of elevated plasma salicylate levels; however, this should not be used in patients with high frequency hearing loss.

Monitoring:

• Monitor for signs and symptoms of bleeding
• Monitor liver function in patients with liver impairment
• Monitor renal function in patients with renal impairment

Patient advice:

• Patients should understand that this drug effects their platelets and may cause them to bruise or bleed more easily; however, any prolonged, unusual or excessive bleed should be reported promptly to their health care provider.
• Patients should be instructed to limit alcohol consumption while taking this drug due an increased risk of bleeding with combined use.
• Patients should be instructed not to abruptly discontinue daily therapy without talking to their health care provider first.
• Patients should be instructed to speak with their healthcare provider if they are pregnant, plan to become pregnant, or are breastfeeding.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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