Aspirin is a versatile drug with a wide range of applications, and understanding its proper dosage is crucial for both adults and pediatric patients. In this guide, we will explore the recommended dosages for different forms and strengths of aspirin, ensuring that you have the knowledge you need to use this medication safely and effectively.
We’ll also delve into special categories, such as individuals with specific medical conditions or unique needs, to help you make informed decisions about aspirin use. Whether you’re looking for guidance on pain relief, heart health, or more, KNOWYOURMEDICINE is here to empower you with the knowledge you need to take control of your health.
Aspirin Dosage Strengths
| Dosages of Aspirin | Adult and Pediatric Dosage Forms and Strengths |
| Tablet | 81 mg, 325 mg, 500 mg |
| Tablet, delayed-release | 162 mg, 325 mg, 500 mg |
| Tablet, chewable | 75 mg, 81 mg |
| Tablet, enteric-coated | 81 mg, 162 mg, 325 mg, 650 mg |
| Gum, Chewing oral | 227 mg |
| Extended-release capsule (Durlaza) | 162.5 mg (adult only) |
| Intravenous | 250 mg, 500 mg |
| Suppository | 60 mg, 120 mg, 200 mg, 300 mg, 600 mg |
Aspirin Adult Dose for Osteoarthritis, Rheumatoid Arthritis and Systemic Lupus Erythematosus
For individuals suffering from rheumatoid arthritis, osteoarthritis, or arthritis and pleurisy associated with systemic lupus erythematosus, the typical starting dose is 3 grams administered orally per day, divided into multiple doses. However, this dosage may need to be adjusted as per the patient’s response and overall efficacy.
It is crucial to note that achieving specific target plasma salicylate levels within the range of 150 to 300 micrograms per milliliter (mcg/mL) is correlated with experiencing the desired anti-inflammatory effects of aspirin.
Care should be taken not to exceed plasma salicylate levels greater than 200 mcg/mL, as this can increase the risk of potential toxicity.
In summary, while these guidelines offer a starting point for aspirin therapy, the unique medical history and requirements of each patient must be taken into account. Consultation with a healthcare provider is essential to ensure that aspirin is administered safely and effectively.
Individualized dosing is essential, as the attainment of target plasma salicylate levels ranging from 150 to 300 mcg/mL is linked to achieving an anti-inflammatory effect. However, it’s important to be cautious, as plasma salicylate levels exceeding 200 mcg/mL can result in potential toxicity.
| Condition | Initial Dose | Maintenance Dose | Comments |
| Rheumatoid Arthritis | 3 g orally per day in divided doses | Adjust dose as needed for efficacy | Attainment of target plasma salicylate levels ranging from 150 to 300 mcg/mL is linked to achieving an anti-inflammatory effect. Plasma salicylate levels exceeding 200 mcg/mL can result in potential toxicity. |
| Osteoarthritis | 3 g orally per day in divided doses | Adjust dose as needed for efficacy | Attainment of target plasma salicylate levels ranging from 150 to 300 mcg/mL is linked to achieving an anti-inflammatory effect. Plasma salicylate levels exceeding 200 mcg/mL can result in potential toxicity. |
| Arthritis and Pleurisy associated with Systemic Lupus Erythematosus | 3 g orally per day in divided doses | Adjust dose as needed for efficacy | Attainment of target plasma salicylate levels ranging from 150 to 300 mcg/mL is linked to achieving an anti-inflammatory effect. Plasma salicylate levels exceeding 200 mcg/mL can result in potential toxicity. |
Aspirin Adult Dose for Fever and Pain
For adults seeking relief from fever or minor pain, aspirin can be administered in various forms. When taken orally, the typical dosage ranges from 300 to 650 milligrams, with the option to repeat every 4 to 6 hours as needed. It’s essential to note that the maximum allowable dose within a 24-hour period should not exceed 4 grams. Alternatively, aspirin can be administered rectally, with a recommended dosage of 300 to 600 milligrams every 4 hours.
Aspirin’s versatility extends to its applications, making it suitable for both fever reduction and temporary pain relief. It can effectively alleviate minor pain resulting from conditions such as headaches, menstrual discomfort, arthritis, muscle pain, or toothaches.
However, it’s advisable to consult with a healthcare professional if you have specific concerns or medical conditions that may influence your aspirin use.
| Route | Dosage | Maximum Dose |
| Oral | 300 to 650 mg every 4 to 6 hours as needed | 4 g in 24 hours |
| Rectal | 300 to 600 mg every 4 hours | N/A |
Aspirin Adult Dose for Myocardial Infarction
In the event of a suspected myocardial infarction, aspirin is typically administered in an immediate-release form. The initial dose ranges from 160 to 162.5 milligrams, taken orally once, as soon as the myocardial infarction is suspected. This rapid action is crucial during such a critical moment. Following the initial dose, a maintenance dose of 160 to 162.5 milligrams should be taken orally once a day for the subsequent 30 days post-infarction.
It’s important to note that extended-release aspirin products are not recommended in situations where a swift onset of action is required, such as in cases of suspected myocardial infarction. In such situations, non-enteric tablets can be chewed or crushed to facilitate immediate effect.
Additionally, it’s worth highlighting that this medication has demonstrated its effectiveness in reducing the risk of vascular mortality in patients with a suspected acute myocardial infarction. After the initial 30-day period, it is advisable to consider secondary prophylaxis as a means of preventing the recurrence of myocardial infarction. This dosing regimen should always be administered under the guidance of a healthcare professional.
| Type | Initial Dose | Maintenance Dose |
| Immediate-Release | 160 to 162.5 mg orally once (suspected MI) | 160 to 162.5 mg orally once a day (30 days post-infarction) |
Aspirin Adult Dose for Ischemic Stroke and Ischemic Stroke – Prophylaxis
The administration of aspirin in the management of ischemic stroke is typically categorized into immediate-release and extended-release forms. For immediate-release, a daily dosage of 50 to 325 milligrams is recommended, taken orally once a day. On the other hand, the extended-release (ER) variant is prescribed at a fixed dose of 162.5 milligrams, also to be taken orally once daily.
Continued therapy is a vital aspect of aspirin use in various medical contexts, including cardiovascular health. The ideal dose for preventing cardiovascular events remains uncertain, but it’s worth noting that higher doses of aspirin are associated with an increased risk of bleeding. Current medical evidence suggests that a low-dose immediate-release (IR) aspirin at a range of 75 to 100 milligrams daily is a suitable option for achieving the desired therapeutic effect with a reduced risk of adverse bleeding events.
Additionally, extended-release (ER) capsules have been specifically designed to slowly release the drug from encapsulated microparticles, thereby extending the absorption process throughout the gastrointestinal tract. Importantly, the pharmacodynamic effect of ER aspirin at 162.5 milligrams is comparable to that which is achieved with immediate-release aspirin at a lower dosage of 81 milligrams.
This information underscores the importance of personalized aspirin therapy guided by healthcare professionals, taking into account the specific health needs and risk factors of each individual.
| Type | Dosage | Uses |
| Immediate-Release | 50 to 325 mg orally once a day | To reduce the risk of death and recurrent stroke in patients who have had ischemic stroke or transient ischemic attack. |
| Extended-Release (ER) | 162.5 mg orally once a day | To reduce the risk of death and recurrent stroke in patients who have had ischemic stroke or transient ischemic attack. |
Aspirin Adult Dose for Angina Pectoris and Angina Pectoris Prophylaxis
Aspirin therapy, whether in the immediate-release (IR) or extended-release (ER) form, plays a significant role in the ongoing management of cardiovascular health. It is recommended to continue this therapy indefinitely. While the precise dosage required to prevent cardiovascular events remains uncertain, it’s important to be aware that higher doses are linked to an increased risk of bleeding. Current medical evidence supports the use of low-dose immediate-release aspirin, particularly in the range of 75 to 100 milligrams daily, as a safe and effective option.
The extended-release capsules have been meticulously engineered to gradually release the medication from encapsulated microparticles, thereby extending its absorption throughout the gastrointestinal tract. Notably, the pharmacodynamic effect of the 162.5 mg extended-release aspirin is comparable to that achieved with 81 mg immediate-release aspirin. This emphasizes the importance of individualized aspirin therapy guided by healthcare professionals, taking into account the unique health needs and risk factors of each patient.
These aspirin dosing regimens are employed with the objective of reducing the combined risk of death and nonfatal myocardial infarction (MI) in patients with unstable angina pectoris, as well as reducing the combined risk of MI and sudden death in patients with chronic stable angina pectoris. Always seek guidance from a healthcare provider to determine the most suitable aspirin regimen for your specific health circumstances.
| Type | Dosage |
| Immediate-Release (IR) | 75 mg to 325 mg orally once a day |
| Extended-Release (ER) | 162 mg orally once a day |
Aspirin Adult Dose for Revascularization Procedures – Prophylaxis
Aspirin plays a crucial role in the post-procedural care of patients who have undergone various revascularization procedures, including coronary artery bypass graft (CABG), percutaneous transluminal coronary angiography (PTCA), and carotid endarterectomy. These procedures require specific aspirin regimens to optimize patient outcomes.
For individuals who have undergone CABG, a dosage of 325 milligrams is typically taken orally once a day, commencing 6 hours after the procedure. This regimen is typically continued for a duration of 1 year.
In the case of PTCA, aspirin is administered at a dose of 325 milligrams orally, 2 hours prior to the procedure, followed by a range of 160 to 325 milligrams orally once a day indefinitely to support ongoing cardiovascular health.
Carotid endarterectomy patients, on the other hand, are usually prescribed 80 milligrams of aspirin taken orally once a day, with the potential for dosage adjustment up to 650 milligrams orally taken twice a day, starting before the surgical procedure and continuing indefinitely.
It’s important to note that current guidelines advise consulting healthcare professionals for the potential use of dual antiplatelet therapy, which combines low-dose aspirin with medications like ticagrelor, clopidogrel, or prasugrel.
These aspirin regimens are employed for patients who have already been prescribed aspirin due to preexisting medical conditions, and they aim to support post-procedural care in those who have undergone revascularization procedures. Always consult with your healthcare provider to determine the most suitable aspirin regimen for your specific health needs and medical history.
| Procedure | Dosing | Duration |
| Coronary Artery Bypass Graft (CABG) | 325 mg orally once a day starting 6 hours after the procedure | Continue for 1 year |
| Percutaneous Transluminal Coronary Angiography (PTCA) | 325 mg orally 2 hours prior to the procedure, then 160 to 325 mg orally once a day indefinitely | Indefinitely |
| Carotid Endarterectomy | 80 mg orally once a day (up to 650 mg orally twice a day) before surgery, continuing indefinitely | Indefinitely |
Aspirin Adult Dose for Ankylosing Spondylitis
The management of spondyloarthropathies often involves aspirin, with an initial recommended dose of up to 4 grams taken orally each day, divided into multiple doses. The key here is flexibility, as the maintenance dose should be adjusted based on the patient’s specific needs to achieve the desired anti-inflammatory effect.
It’s important to highlight that dosages should be tailored to each individual, and close monitoring is advised. In order to strike the right balance between effectiveness and safety, the target plasma salicylate levels typically fall in the range of 150 to 300 micrograms per milliliter (mcg/mL), as this is associated with an anti-inflammatory response. However, exceeding plasma salicylate levels greater than 200 mcg/mL can lead to a higher risk of potential toxicity.
| Condition | Initial Dose | Maintenance Dose |
| Ankylosing Spondylitis | Up to 4 g orally per day in divided doses | Adjust dose as needed for anti-inflammatory efficacy |
Aspirin Adult Dose for Myocardial Infarction – Prophylaxis and Cardiovascular Risk Reduction
For primary prophylaxis, individuals who are 50 years or older typically take 75 to 100 milligrams of aspirin orally once a day to reduce the risk of a first heart attack. For adults with type 1 or type 2 diabetes who are at an increased risk of cardiovascular disease (CVD), a daily dosage of 75 to 162 milligrams is recommended to lower the risk of heart-related events.
For adults aged 50 to 59 with a 10% or higher 10-year risk of cardiovascular disease, who do not face an elevated risk of bleeding and have a life expectancy of at least a decade, the United States Preventive Services Task Force (USPSTF) suggests considering the initiation of low-dose aspirin for primary prevention against atherosclerotic cardiovascular disease (ASCVD) and colorectal cancer (CRC).
When it comes to adults between 60 to 69 years, the decision to commence primary prophylaxis should follow similar criteria and factor in an individualized assessment of risk. However, for adults aged 70 or older, the current available evidence is inadequate to gauge the overall balance between the benefits and potential drawbacks.
In alignment with the American Diabetes Association Standards of Care, primary prophylaxis is advised for adults with diabetes who are at an increased risk of CVD. This typically includes most patients aged 50 or older who possess at least one additional significant risk factor. For individuals under 50 years of age, the decision necessitates clinical judgment.
In the context of secondary prophylaxis, immediate-release aspirin is typically administered at a dose ranging from 75 to 325 milligrams taken orally once a day. Alternatively, extended-release aspirin, at a dosage of 162.5 milligrams, is taken orally once a day. These secondary prophylaxis regimens aim to reduce the risk of recurrent myocardial infarction.
The ideal aspirin dosage for preventing cardiovascular events remains uncertain; nonetheless, it’s important to acknowledge that higher doses are linked to an elevated risk of bleeding. Based on current evidence, the use of low-dose immediate-release (IR) aspirin at a range of 75 to 100 milligrams daily is recommended to strike a balance between effectiveness and safety.
Extended-release (ER) capsules have been engineered to gradually release the drug from encapsulated microparticles, thereby prolonging its absorption throughout the gastrointestinal tract. Notably, the pharmacodynamic effect of ER aspirin at 162.5 milligrams is comparable to that achieved with 81 milligrams of immediate-release aspirin.
This therapy is primarily employed to reduce the combined risk of death and nonfatal myocardial infarction (MI) in patients dealing with chronic coronary artery disease, such as those who have previously experienced an MI. It’s essential to consider these dosing recommendations under the guidance of a healthcare professional to ensure a suitable and effective approach to treatment.
| Type | Dosage | Dose Frequency |
| Primary Prophylaxis (50 years or older) | 75 to 100 mg | Orally once a day |
| Primary Prophylaxis (Adults with type 1 or type 2 diabetes at increased CVD risk) | 75 to 162 mg | Orally once a day |
| Secondary Prophylaxis (Immediate-Release – IR) | 75 mg to 325 mg | Orally once a day |
| Secondary Prophylaxis (Extended-Release – ER) | 162.5 mg | Orally once a day |
Aspirin Adult Dose for Colorectal Cancer
For individuals aged 50 years or older: A daily oral dose of 75 to 100 mg.
It’s important to note that aspirin therapy for colorectal cancer prevention aligns with broader recommendations based on age and specific risk factors. In adults aged 50 to 59 years with a 10% or greater 10-year risk of cardiovascular disease (CVD), low-dose aspirin is recommended by the United States Preventive Services Task Force (USPSTF) for primary prevention against both atherosclerotic cardiovascular disease (ASCVD) and colorectal cancer (CRC).
For those in the 60 to 69 age group, the decision to initiate primary prophylaxis should consider similar factors while also being tailored to individual risk. However, for adults aged 70 or older, the available evidence is currently insufficient to assess the balance between benefits and potential risks.
In summary, this aspirin regimen primarily serves the purpose of primary prevention against colorectal cancer. Always consult with a healthcare professional to determine the most appropriate aspirin therapy for your individual health profile and circumstances.
| Age Group | Dosage |
| 50 years or older | 75 to 100 mg orally once a day |
Aspirin Pediatric Dose for Fever and Pain
For children aged 12 years or older: The recommended oral dosage ranges from 300 to 650 milligrams, to be taken every 4 to 6 hours as needed. The maximum allowable dose within a 24-hour period should not exceed 4 grams.
It’s crucial to be aware that aspirin should be avoided in pediatric patients who are experiencing viral illnesses due to the risk of Reye’s syndrome. This therapy is typically employed as a temporary means to reduce fever or for the temporary relief of minor pain arising from conditions such as headaches, menstrual discomfort, arthritis, muscle pain, or toothaches. Always consult with a healthcare professional when considering the use of aspirin in pediatric patients to ensure it’s suitable for the specific health needs and circumstances.
| Age Group | Dosage | Maximum Daily Dose |
| 12 years or older | 300 to 650 mg orally every 4 to 6 hours as needed | 4 g in 24 hours |
Aspirin Pediatric Dose for Juvenile Rheumatoid Arthritis
The recommended dosing for juvenile rheumatoid arthritis in pediatric patients involves an initial dose of 90 to 130 mg/kg, administered orally and divided into multiple doses. The maintenance dose should be adjusted as necessary to achieve the desired anti-inflammatory effect.
It’s crucial to emphasize that dosing should be tailored to each individual patient, and careful monitoring is essential. The goal is to maintain target plasma salicylate levels in the range of 150 to 300 micrograms per milliliter (mcg/mL) to ensure an effective anti-inflammatory response, while avoiding higher plasma salicylate levels exceeding 200 mcg/mL, which are associated with an increased risk of potential toxicity.
This treatment is primarily intended for alleviating the signs and symptoms of juvenile rheumatoid arthritis in pediatric patients. Always consult with a healthcare professional to determine the most appropriate approach for your child’s specific health needs and circumstances.
| Condition | Initial Dose | Maintenance Dose |
| Juvenile Rheumatoid Arthritis | 90 to 130 mg/kg orally in divided doses | Increase as needed for anti-inflammatory efficacy |
Aspirin Pediatric Dose for Kawasaki Disease
The standard pediatric dosing regimen for Kawasaki disease involves an initial phase where patients are administered 80 to 100 mg/kg of aspirin orally, divided into multiple doses, over a period of up to 14 days. This initial phase serves as an anti-inflammatory treatment.
Subsequently, there is a follow-up phase where children receive 1 to 5 mg/kg of aspirin orally per day for a duration of 6 to 8 weeks, serving as an antiplatelet therapy.
It’s important to note that, for optimal management of Kawasaki disease, Intravenous Immune Globulin is recommended within the first 10 days of symptom onset. In cases where children have moderate or giant coronary aneurysms following Kawasaki disease, additional treatment with warfarin may be necessary in conjunction with low-dose aspirin, and it’s advisable to refer to established guidelines for guidance.
For children who develop giant aneurysms and experience acute coronary artery thrombosis, medical interventions like thrombolysis or acute surgical procedures are recommended.
| Phase | Dosing | Duration | Purpose |
| Initial (Acute Phase) | 80 to 100 mg/kg orally in divided doses for up to 14 days | During the acute phase of the disease | Anti-inflammatory agent |
| Followed by | 1 to 5 mg/kg orally per day for 6 to 8 weeks | Following the acute phase for an extended period | Antiplatelet agent |
Aspirin Pediatric Dose for Thrombotic/Thromboembolic Disorder
The prescribed pediatric dosage for thrombotic/thromboembolic disorders is typically 1 to 5 milligrams per kilogram, administered orally once a day.
It’s important to note that guidance on aspirin’s use as antithrombotic therapy in neonates and children is provided by the American College of Chest Physicians, and their evidence-based guidelines should be referred to for further direction. Aspirin may be considered for neonates with recurrent Arterial Ischemic Stroke (AIS).
For children experiencing acute AIS, with or without thrombophilia, aspirin may serve as initial therapy until the exclusion of dissection and embolic causes. Once dissection and cardioembolic causes have been ruled out, daily aspirin prophylaxis should continue for a minimum of 2 years.
Aspirin might also be employed for thromboprophylaxis in neonates and children after Modified Blalock-Taussig Shunts (MBTS) surgery and in children after Fontan surgery. In cases involving Ventricular Assist Devices (VADs) in children, antiplatelet therapy (either aspirin or aspirin and dipyridamole) should begin within 72 hours of VAD placement.
Additionally, for children with acute AIS secondary to non-Moyamoya vasculopathy, aspirin may be considered as an initial therapy option for a duration of 3 months, and ongoing antithrombotic therapy should be guided by repeat cerebrovascular imaging. For children with acute AIS secondary to Moyamoya, aspirin therapy should be taken into consideration, and children should be referred to an appropriate center for evaluation regarding revascularization.
| Condition | Dosage |
| Thrombotic/Thromboembolic Disorder | 1 to 5 mg/kg orally per day |
Aspirin Renal Dose Adjustments
These renal dose adjustments are essential for individuals with varying levels of renal function when considering aspirin therapy. If the creatinine clearance (CrCl) is less than 10 mL/min, aspirin is contraindicated, meaning it should not be used. If the CrCl is 10 mL/min or greater, aspirin can be used, but with caution, and the dosage may need to be adjusted based on the patient’s specific renal function and other factors, as determined by a healthcare professional.
| Renal Function (CrCl) | Dosage Adjustment |
| Less than 10 mL/min | Contraindicated |
| 10 mL/min or greater | Use with caution |
Aspirin Liver Dose Adjustments
- For individuals with severe hepatic impairment, aspirin is contraindicated, meaning it should not be used.
- For those with mild to moderate hepatic impairment, aspirin should be used with caution.
Aspirin Dialysis Dose Adjustments
- Hemodialysis is an effective method for removing salicylate in cases of overdose, and aspirin administration may be considered after hemodialysis. Close monitoring for bleeding is advisable.
- In peritoneal dialysis, aspirin concentrations may be reduced.
Administration Advice
- Consume with a full glass of water, unless fluid intake is limited. To alleviate gastrointestinal discomfort, you may take it with or after meals.
Extended-Release Capsule
- Take it at roughly the same time every day. Swallow the capsules whole; do not break, crush, or chew them. Avoid taking it within 2 hours before or 1 hour after consuming alcohol.
Enteric Coated
- Do not crush or chew this type of aspirin.
Suppository
- Remove the suppository from its plastic packet and insert it into the rectum as deeply as possible.
- These instructions are provided to ensure the safe and effective use of aspirin in various formulations, whether in capsule, enteric-coated, or suppository form. Always follow these guidelines as directed by your healthcare professional.
