Aspirin: Side Effects, Uses, Dosage, Interactions, Warnings (2024)

• Uses
  • What Is Aspirin and How Does It Work?
• Dosages
  • What Are Dosages of Aspirin?
• Side Effects
  • What Are Side Effects Associated with Using Aspirin?
• Drug Interactions
  • What Other Drugs Interact with Aspirin?
• Warnings and Precautions
  • What Are Warnings and Precautions for Aspirin?

What Is Aspirin and How Does It Work?

Aspirin is used to reduce fever and relieve mild to moderate pain from conditions such as muscle aches, toothaches, common cold, and headaches. It may also be used to reduce pain and swelling in conditions such as arthritis. Aspirin is known as a salicylate and a nonsteroidal anti-inflammatory drug (NSAID). It works by blocking a certain natural substance in your body to reduce pain and swelling. Consult your doctor before treating a child younger than 12 years.

Your doctor may direct you to take a low dose of aspirin to prevent blood clots. This effect reduces the risk of stroke and heart attack. If you have recently had surgery on clogged arteries (such as bypass surgery, carotid endarterectomy, coronary stent), your doctor may direct you to use aspirin in low doses as a "blood thinner" to prevent blood clots.

Aspirin is available under the following different brand names: Zorprin, Bayer Buffered Aspirin, Durlaza, Asatab, Adprin-B, Alka-Seltzer Extra Strength with Aspirin, Alka-Seltzer with Aspirin, Arthritis Pain Formula, Ascriptin, Ascriptin Maximum Strength, ASA, Bayer Children's Aspirin, Bayer Women's Low Dose, Bayer Low Adult Strength, Bayer Advanced Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bufferin, Bufferin Extra Strength, Ecotrin, Ecotrin Maximum Strength, Empirin, Extended Release Bayer 8-Hour Caplets, Extra Strength Bayer Plus Caplets, Genuine Bayer Aspirin, Halfprin, Maximum Bayer Aspirin, St. Joseph Adult Chewable Aspirin, St. Joseph Regular Strength, and acetylsalicylic acid.

What Are Dosages of Aspirin?

Dosages of Aspirin

Adult and Pediatric Dosage Forms and Strengths

Tablet

• 81 mg
• 325 mg
• 500 mg

Tablet, delayed-release

• 162mg
• 325mg
• 500mg

Tablet, chewable

• 75 mg
• 81 mg

Tablet, enteric-coated

• 81 mg
• 162 mg
• 325 mg
• 650 mg

Gum, chewing, oral

• 227 mg

The extended-release capsule (Durlaza [Rx]) (adult only)

• 162.5 mg

Dosage Considerations – Should be Given as Follows:

Pain and Fever

• Adults: 325-650 mg orally/rectally once every 4-6 hours as needed
• Controlled/extended/delayed-release products (enteric-coated): 650-1300 mg orally once every 8 hours; not to exceed 3.9 g/day

Children under 12 years:

• 10-15 mg/kg orally once every 4 hours, up to 60-80 mg/kg/day

Children 12 years and older:

• 325-650 mg orally/rectally once every 4-6 hours as needed

Controlled/extended/delayed-release products (enteric-coated): 650-1300 mg orally once every 8 hours; not to exceed 3.9 g/day

Acute Coronary Syndrome

For use as adjunctive antithrombotic effects for ACS (ST-segment elevation myocardial infarction [STEMI], unstable angina [UA]/non-ST-segment elevation myocardial infarction [NSTEMI])

Acute symptoms

• 160-325 mg orally; chew non-enteric-coated tablet upon presentation (within minutes of symptoms)
• If unable to take orally, may give 300-600 mg rectal suppository

Maintenance (secondary prevention)

• 75-81 mg orally once/day indefinitely (preferred dose); may give 81-325 mg/day
• Regimen may depend on co-administered drugs or comorbid conditions
• Co-administered with ticagrelor: 81 mg orally once/day

Percutaneous transluminal coronary angioplasty

• Adjunctive aspirin therapy to support reperfusion with primary PCI (with or without fibrinolytic therapy)
• Preoperative dose: 162-325 mg orally before the procedure
• Maintenance: 81 mg orally once/day indefinitely (preferred dose) may give 81-325 mg/day
• The regimen may depend on co-administered drugs or comorbid conditions
• Co-administered with ticagrelor: 81 mg orally once/day

Primary and Secondary Prevention

Durazo: Indicated to reduce the risk of death and heart attack (myocardial infarction/MI) in patients with chronic CAD (e.g., history of MI, unstable angina, or chronic stable angina); also indicated to reduce the risk of death and recurrent stroke in patients who have had an ischemic stroke or transient ischemic attack (TIA)

The extended-release capsule (Durlaza [Rx]): 162.5 mg orally once/day

Use immediate-release aspirin, not extended-release capsule in situations where a rapid onset of action is required (such as acute treatment of myocardial infarction or before percutaneous coronary intervention)

Ischemic Stroke and Transient Ischemic Attack

• 50-325 mg/day orally within 48 hours of stroke or TIA, then 75-100 mg/day orally

Osteoarthritis

• Up to 3 g/day orally in divided doses

Rheumatoid Arthritis

• 3 g/day orally in divided doses; increased as needed for anti-inflammatory efficacy (target plasma salicylate, 150-300 mcg/mL)

Juvenile Rheumatoid Arthritis

• Children less than 25 kg: 60-100 mg/kg/day orally divided every 6-8 hours (maintain serum salicylate at 150-300 mcg/mL)
• Children 25 kg or more: 2.4-3.6 g/day

Spondyloarthropathy

• 3.6-5.4 g/day orally in divided doses; monitor serum concentrations

Kawasaki Disease (Pediatric)

• Febrile phase: 80-100 mg/kg/day orally divided every 6 hours for up to 14 days (48-72 hours after fever abates)
• Maintenance: 3-6 mg/kg/day orally in single dose

Colorectal Cancer (Off-label)

Prophylaxis

• 600 mg/day orally
• Decreases risk of developing hereditary colorectal cancer (i.e., Lynch syndrome) by 60% if taken daily for at least 2 years

Dosing Modifications

Renal impairment

• CrCl greater than 10 mL/min: Dose adjustment not necessary
• CrCl less than 10 mL/min: Not recommended

Hepatic impairment

Severe liver disease: Not recommended

Dosing Considerations, Pediatric

• Toxic dose: 200 mg/kg

What Are Side Effects Associated with Using Aspirin?

Side effects of aspirin include:

• Skin swelling
• Bronchospasm
• Central nervous system (CNS) alteration
• Skin problems
• Gastrointestinal (GI) pain, ulceration, bleeding
• Liver damage
• Hearing loss
• Nausea
• Platelet aggregation inhibition
• Premature hemolysis
• Pulmonary edema (salicylate-induced, non-cardiogenic)
• Rash
• Kidney damage
• Ringing in the ears (tinnitus)
• Hives
• Vomiting

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What Other Drugs Interact with Aspirin?

If your doctor has directed you to use this medication for diabetes, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.

Severe interactions of Aspirin include:

• dichlorphenamide
• mifepristone

Serious iteractions of Aspirin include:

• benazepril
• captopril
• enalapril
• fosinopril
• ibuprofen
• ketorolac
• ketorolac intranasal
• lesinurad
• lisinopril
• measles, mumps, rubella and varicella vaccine, live
• methotrexate
• moexipril
• pemetrexed
• perindopril
• probenecid
• quinapril
• ramipril
• ticlopidine
• trandolapril
• varicella virus vaccine live

Aspirin has moderate interactions with at least 257 different drugs.

Aspirin has mild interactions with at least 120 different drugs.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

What Are Warnings and Precautions for Aspirin?

Warnings

This medication contains aspirin. Do not take Zorprin, Bayer Buffered Aspirin, Durlaza, Asatab, Adprin-B, Alka-Seltzer Extra Strength with Aspirin, Alka-Seltzer with Aspirin, Arthritis Pain Formula, Ascriptin, Ascriptin Maximum Strength, ASA, Bayer Children's Aspirin, Bayer Women's Low Dose, Bayer Low Adult Strength, Bayer Advanced Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bufferin, Bufferin Extra Strength, Ecotrin, Ecotrin Maximum Strength, Empirin, Extended Release Bayer 8-Hour Caplets, Extra Strength Bayer Plus Caplets, Genuine Bayer Aspirin, Halfprin, Maximum Bayer Aspirin, St. Joseph Adult Chewable Aspirin, St. Joseph Regular Strength, or acetylsalicylic acid if you are allergic to aspirin or any ingredients contained in this drug.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.

Contraindications

Hypersensitivity to aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs); aspirin-associated hypersensitivity reactions include aspirin-induced urticaria (HLA-DRB1*1302-DQB1*0609 haplotype), aspirin-intolerant asthma (HLA-DPB1*0301)

Allergy to tartrazine dye

Absolute

• Bleeding GI ulcers, hemolytic anemia from pyruvate kinase (PK) and glucose-6-phosphate dehydrogenase (G6PD) deficiency, hemophilia, hemorrhagic diathesis, hemorrhoids, lactating mother, nasal polyps associated with asthma, sarcoidosis, thrombocytopenia, ulcerative colitis

Relative

• Appendicitis, asthma (bronchial), chronic diarrhea, bowel outlet obstruction (for enteric-coated formulations), dehydration, erosive gastritis, hypoparathyroidism

Effects of Drug Abuse

None.

Short-Term Effects

See "What Are Side Effects Associated with Using Aspirin?"

Long-Term Effects

See "What Are Side Effects Associated with Using Aspirin?"

Cautions

Anemia, GI malabsorption, history of peptic ulcers, gout, hepatic disease, hypochlorhydria, hypoprothrombinemia, renal impairment, thyrotoxicosis, vitamin K deficiency, renal calculi, ethanol use (may increase bleeding).

Discontinue therapy if tinnitus develops.

Should be taken with food or 8-12 oz of water to avoid GI effects.

Not indicated for children with viral illness; use of salicylates in pediatric patients with varicella or influenza-like illness is associated with increased incidence of Reye syndrome.

Heart Failure (HF) risk:

• NSAIDs have the potential to trigger HF by prostaglandin inhibition that leads to sodium and water retention, increased systemic vascular resistance, and blunted response to diuretics
• High-dose aspirin (greater than 325mg) should be avoided or withdrawn whenever possible
• AHA/ACC Heart Failure Guidelines; Circulation. 2016; 134

Pregnancy and Lactation

Use aspirin with caution during the first and second trimesters of pregnancy if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

Use aspirin only in LIFE-THREATENING emergencies in the third trimester when no safer drug is available. There is positive evidence of human fetal risk. It is especially important that patient not use aspirin during last 3 months of pregnancy unless specifically directed to do so by doctor, because it may cause problems in unborn child or complications during delivery.

Aspirin enters breast milk; a decision should be made regarding whether to discontinue nursing or to discontinue drug, taking into account importance of drug to mother.