Acetylsalicylic acid

ATC code

B01AC06

Therapeutic class

Antithrombotic agent · Platelet aggregation inhibitor

Forms

oral tablet

Brand names

Aspirina (ES) · Aspirinetas (AR) · A.A.S. (ES) · Aspirin (US) · Adiro (ES)

Overall confidence

medium

Regulatory sources consulted

Approved indications

Secondary prevention of myocardial infarction, ischemic stroke, and other cardiovascular events in high-risk patients (e.g., stable angina, history of TIA).
Management of obstetric antiphospholipid syndrome to prevent pregnancy complications, usually in combination with low-molecular weight heparin. · off-label

Contraindications

Absolute

Hypersensitivity to salicylates or NSAIDs, active peptic ulcer, bleeding diathesis, severe renal/hepatic/cardiac failure, third trimester of pregnancy.
Concomitant use with methotrexate at doses ≥ 15 mg/week.

Clinical warnings

Major warning · Risk of gastrointestinal bleeding. Use with caution in patients with a history of ulcers or bleeding disorders. — AEMPS CIMA
Major warning · Reye's Syndrome: Should not be given to children or adolescents with viral infections (chickenpox, flu) due to the risk of developing Reye's syndrome. — AEMPS CIMA

Drug interactions

HighMethotrexateL01BA01
Mechanism: Decreased renal clearance of methotrexate, increasing its hematological toxicity.
Recommendation: Contraindicated with methotrexate doses ≥ 15 mg/week. Monitor closely with lower doses.
AEMPS CIMA
ModerateIbuprofenM01AE01
Mechanism: Ibuprofen may antagonize the irreversible antiplatelet effect of low-dose aspirin, limiting its cardioprotective benefit.
Recommendation: If ibuprofen use is required, administer it at least 30 minutes after or >8 hours before immediate-release aspirin.
AEMPS CIMA

Adverse events

Common (≥1%)

dyspepsia · gastrointestinal pain · increased bleeding time · epistaxis · gingival bleeding

Rare but serious

severe gastrointestinal bleeding · intracranial hemorrhage · Reye's syndrome · anaphylactic reactions · thrombocytopenia

Pregnancy and lactation

FDA category: D (3rd trimester: X)

Contraindicated in the 3rd trimester. Low doses (75-100 mg) are used under medical supervision for specific indications like pre-eclampsia prevention or in antiphospholipid syndrome. High doses can cause fetal toxicity. Lactation: With low doses (75-325 mg/day), salicylate levels in milk are low; monitor infant for bruising or bleeding. Avoid continuous high doses.

Recent literature (PubMed)

Obstetric antiphospholipid syndrome.
Soto-Peleteiro A, et al. · Med Clin (Barc) · 2024 · Relevance 4/5
Revisión sobre el síndrome antifosfolípido obstétrico que destaca la aspirina a dosis bajas, a menudo con heparina, como la base del tratamiento para prevenir complicaciones. También aborda la seguridad de la aspirina a dosis bajas durante la lactancia, señalando que los niveles en leche materna son bajos.
Statin and aspirin use in parasitic infections as a potential therapeutic strategy: A narrative review.
Burgess V, et al. · Rev Argent Microbiol · 2023 · Relevance 2/5
Revisión narrativa que explora el uso de estatinas y aspirina en infecciones parasitarias. Concluye que, si bien las estatinas pueden ser un adyuvante factible, no hay evidencia experimental sólida para el uso de aspirina en este contexto, y se necesitan más estudios.