Aspirin: Dosage, Side Effects, Brands & Clinical Use | MedexInfo

Aspirin

OTC / Rx

Therapeutic ClassNSAID, Antiplatelet

Common Dose75–325 mg daily for cardiovascular prevention; 325–650 mg every 4–6 hr for pain/fever

Max / 24h4 g (pain/fever), 325 mg (CV prevention)

PregnancyCategory C/D depending on trimester

Indications ▼

Mild to moderate pain (headache, musculoskeletal pain)

Fever reduction

Inflammatory conditions (rheumatoid arthritis, osteoarthritis)

Prevention of myocardial infarction, stroke, and other thromboembolic events

Mechanism & Pharmacokinetics ▼

Mechanism: Irreversibly inhibits cyclooxygenase (COX-1 and COX-2), reducing prostaglandin synthesis (analgesic, anti-inflammatory, antipyretic) and platelet aggregation (antiplatelet effect).

Pharmacokinetics: Rapidly absorbed orally (Tmax 0.5–2 hrs), extensively metabolized in liver; excreted via urine. Half-life ~15–20 min (acetylated form), platelet effect lasts ~7–10 days.

Dosage & Administration ▼

Indication	Recommended Dose	Max / 24h
Cardiovascular prevention	75–325 mg once daily	325 mg
Pain / Fever	325–650 mg every 4–6 hr	4 g
Anti-inflammatory	3–4 g daily in divided doses	4 g

Take with food or milk to reduce GI irritation. Enteric-coated tablets reduce gastric irritation but may delay onset.

Side Effects ▼

Common: gastrointestinal discomfort, nausea, heartburn

Serious: GI bleeding, ulceration, hemorrhagic stroke, hypersensitivity reactions

Rare: Reye’s syndrome in children, tinnitus (high doses), renal impairment

Contraindications ▼

Hypersensitivity to aspirin or NSAIDs

Active peptic ulcer or GI bleeding

Children or adolescents with viral infections (risk of Reye’s syndrome)

Severe hepatic or renal impairment

Drug Interaction ▼

Anticoagulants (warfarin, heparin) – increased bleeding risk

Other NSAIDs – additive GI toxicity

ACE inhibitors/ARBs – may reduce antihypertensive effect

Alcohol – increased risk of GI bleeding

Pregnancy & Lactation ▼

Use with caution during first and second trimesters (Category C)

Avoid in third trimester (Category D) due to risk of fetal ductus arteriosus closure

Use in breastfeeding only if benefits outweigh risks

Clinical / Research Summary ▼

Cardiovascular Prevention: Low-dose aspirin reduces risk of myocardial infarction, stroke, and vascular death by irreversibly inhibiting platelet aggregation.

Analgesic & Antipyretic Effect: Provides reliable pain relief and fever reduction via inhibition of prostaglandin synthesis.

Anti-Inflammatory: Effective in rheumatoid arthritis and other inflammatory disorders at higher doses.

Research Insights: Long-term low-dose aspirin is widely used for secondary prevention of cardiovascular events; risk of GI bleeding requires careful patient selection.

Patient Counseling Points ▼

Take with food or milk to reduce stomach upset

Do not crush enteric-coated tablets

Inform doctor about all medications, especially anticoagulants

Seek medical advice if GI bleeding, unusual bruising, or persistent pain occurs

Avoid in children with viral infections

Storage & Handling ▼

Store at 15–30°C; protect from moisture and light

Keep out of reach of children

Brand Names (Bangladesh & Global) ▼

Bangladesh (Local Brands):

Disprin Aspirin Aspro

Global / International Brands:

Bayer Aspirin Ecotrin Bufferin

Medical Disclaimer: This clinical summary is for informational purposes only. Always follow guidance from a qualified healthcare professional for dosage, interactions, and use.

Reference Hubs:

• Drug Class: NSAID & Antiplatelet • Conditions: Cardiovascular Prevention • Pathway: Prostaglandin Synthesis & Platelet Aggregation • Clinical Evidence & Trials