1. Clinical & Scientific Overview
Aspirin (Acetylsalicylic Acid — Low-Dose Antiplatelet) (TIP-MED-000018, Reference Code [3.18]) is classified under
Cardiovascular & Antithrombotic Medicines (Ch 03) as a Irreversible Cyclooxygenase-1 (COX-1) Inhibitor; Thromboxane A2 Synthesis Inhibitor (Antiplatelet).
Within the Indian regulatory and compendial framework, it is governed under Schedule H Prescription Drug (To be sold by retail on the prescription of a Registered Medical Practitioner only — Drugs Rules 1945).
Dytor (Cipla), Tide (Torrent)
Enteric-Coated (EC / Gastro-resistant) Tablets: 75 mg, 150 mg, 325 mg; Dispersible Tablets (for acute ACS loading): 150 mg, 300 mg, 325 mg
3. Mechanism of Action & Pharmacodynamics
Irreversible Cyclooxygenase-1 (COX-1) Inhibitor; Thromboxane A2 Synthesis Inhibitor (Antiplatelet) acting on target receptor/enzyme pathways in Cardiovascular & Antithrombotic Medicines (Ch 03): clinical efficacy is mediated via Irreversible Cyclooxygenase-1 (COX-1) Inhibitor; Thromboxane A2 Synthesis Inhibitor (Antiplatelet) for Secondary prevention of myocardial infarction, unstable/stable angina, post-PCI (coronary stenting—as part of Dual Antiplatelet Therapy [DAPT]), post-CABG, and non-cardioembolic ischaemic stroke / TIA; acute loading in suspected MI..
4. Therapeutic Indications & Evidence-Supported Uses
- Secondary prevention of myocardial infarction, unstable/stable angina, post-PCI (coronary stenting—as part of Dual Antiplatelet Therapy [DAPT]), post-CABG, and non-cardioembolic ischaemic stroke / TIA
- acute loading in suspected MI
🇮🇳 Jurisdiction & Indication Note: Indications and schedules reflect Indian compendial and regulatory records (CDSCO / Indian Pharmacopoeia & NFI / NLEM 2022). Where international reference labels (US FDA DailyMed / NCBI StatPearls) are cited for pharmacokinetic or mechanistic parameters, international approvals do not automatically imply CDSCO approval in India.
5. Educational Dosage Context, Formulations & Administration
Educational Dosing & Regimen Summary: General Adult Reference: Chronic Maintenance: 75 mg to 150 mg once daily (75 mg OD is standard long-term maintenance). Acute MI Loading: 150 mg–325 mg non-enteric (or chewed EC) STAT. Follow physician prescription.
Administration & Meal Timing: Take WITH or immediately AFTER food (usually after lunch or after breakfast/dinner) with a full glass of water to minimise gastroduodenal mucosal irritation. | Once daily after a main meal (commonly after lunch in Indian cardiology prescriptions, or at night if combined with a statin in Ecosprin-AV).
6. Pharmacokinetics, Metabolism & Renal/Hepatic Adjustment
Absorption, distribution, metabolism, and excretion follow class pharmacokinetic profile; verify patient renal/hepatic function.
Renal: Safe at 75 mg antiplatelet dose in mild-to-moderate CKD, but avoid in severe renal failure (CrCl <10–15 mL/min) unless specifically indicated with bleeding precautions. Hepatic: Avoid in severe liver disease with coagulopathy or portal hypertension/varices.
Renal: Safe at 75 mg antiplatelet dose in mild-to-moderate CKD, but avoid in severe renal failure (CrCl <10–15 mL/min) unless specifically indicated with bleeding precautions. Hepatic: Avoid in severe liver disease with coagulopathy or portal hypertension/varices.
Renal: Safe at 75 mg antiplatelet dose in mild-to-moderate CKD, but avoid in severe renal failure (CrCl <10–15 mL/min) unless specifically indicated with bleeding precautions. Hepatic: Avoid in severe liver disease with coagulopathy or portal hypertension/varices.
7. Contraindications, Precautions & High-Risk Warnings
- Contraindicated in active peptic ulceration, haemophilia/bleeding disorders, aspirin-exacerbated respiratory disease (AERD / Samter's triad in asthmatics), severe thrombocytopenia (including Dengue fever!), and children <16 years (Reye's syndrome). Caution in elderly >70 years without established ASCVD (not recommended for routine primary prevention due to GI/intracranial bleed risk).
Key Clinical Precautions: Renal: Safe at 75 mg antiplatelet dose in mild-to-moderate CKD, but avoid in severe renal failure (CrCl <10–15 mL/min) unless specifically indicated with bleeding precautions. Hepatic: Avoid in severe liver disease with coagulopathy or portal hypertension/varices.
8. Adverse Effects Profile
- Dyspepsia, epigastric burning, easy skin bruising (ecchymoses), prolonged minor bleeding from cuts or gums, epistaxis.
- Upper gastrointestinal haemorrhage (haematemesis or black tarry melaena stools), peptic ulcer perforation, haemorrhagic stroke, severe bronchospasm in aspirin-sensitive asthmatics.
- Monitor for severe hypersensitivity, organ toxicity, or dose-limiting adverse events.
9. Major Drug–Drug, Drug–Food & Drug–Herb Interactions
- Ibuprofen / Naproxen Interaction: Ibuprofen competitively binds the platelet COX-1 channel and blocks aspirin's irreversible antiplatelet effect if taken before aspirin (give immediate-release aspirin ≥30 min before ibuprofen or ≥8 hours after, or avoid NSAIDs altogether)
- Additive major bleeding risk with clopidogrel, prasugrel, ticagrelor, warfarin, apixaban, rivaroxaban, SSRIs (sertraline/escitalopram), and corticosteroids
- Reduces uricosuric at low doses and decreases methotrexate renal clearance
10. Clinical Monitoring, Patient Counselling & Storage
Clinical & Laboratory Monitoring: Monitor clinical response, baseline renal/hepatic parameters, and relevant serum biomarkers.
Pharmacist Patient Counselling Points:
- Patient Counselling Checklist: Swallow Enteric-Coated (Ecosprin) tablets whole after a meal—do not crush or chew (except during an emergency heart attack when a doctor directs chewing 300 mg immediately). Warn patients to inform dentists and surgeons at least 5–7 days before planned procedures, and to watch for black, tar-like stools or coffee-ground vomiting. During seasonal Dengue outbreaks in India, immediately consult the doctor if fever with falling platelets occurs.
- Meal & Clock Timing Instruction: Take WITH or immediately AFTER food (usually after lunch or after breakfast/dinner) with a full glass of water to minimise gastroduodenal mucosal irritation. (Once daily after a main meal (commonly after lunch in Indian cardiology prescriptions, or at night if combined with a statin in Ecosprin-AV).)
- Missed Dose Protocol: Take after food as soon as remembered on the same day; if remembered the next day, skip the missed dose and take only the scheduled daily tablet. Never double the dose.
- Geriatric Dispensing Pearl: Elderly patients (>65 years) taking aspirin—especially Dual Antiplatelet Therapy (Aspirin + Clopidogrel) or Aspirin + Steroid/SSRI—should routinely be co-prescribed a Proton Pump Inhibitor (e.g., pantoprazole) for gastroprotection.
Storage, Stability & Dispensing Safeguards: Store below 25°C–30°C in original moisture- and light-resistant packaging out of reach of children. Available forms: Enteric-Coated (EC / Gastro-resistant) Tablets: 75 mg, 150 mg, 325 mg; Dispersible Tablets (for acute ACS loading): 150 mg, 300 mg, 325 mg
11. Visual Pharmacology & Mechanism Diagram (svg-v339-01-adme-12-step-journey)
12. Authoritative References, Regulatory Sources & Editorial Disclaimer
Primary Compendial & Guideline Reference: Indian Pharmacist Desk Reference — Professional Edition 2.7 (2026–27) • Ch 03 [3.18] (p. 29)
Official Verification Portals: Indian Pharmacopoeia Commission (IPC) & National Formulary of India (NFI) • Central Drugs Standard Control Organization (CDSCO) • Ministry of Health & Family Welfare — NLEM 2022 • NCBI Bookshelf / StatPearls Pharmacology Reference • DailyMed (US FDA Official Prescribing Reference)
Last Medically & Pharmaceutically Reviewed: 2026-11-10 • Verification Status: HANDBOOK_SOURCE_CONTENT
Educational & Clinical Disclaimer: This reference profile is published solely for pharmacy education, academic study, and professional clinical reference. It does not substitute for patient-specific clinical judgement, qualified specialist oncology/medical supervision, or official CDSCO/IP prescribing information. Never self-medicate with prescription, Schedule H/H1/X, NDPS, or oncology medicines.
13. Related Reference Monographs, Educational Guides & Visual Concept
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