Aspirin works by irreversibly inhibiting cyclooxygenase-1 and 2 (COX-1 and 2) enzymes. It has antipyretic, analgesic, and anti-inflammatory properties.

Aspirin Uses:

It is indicated in the treatment of the following conditions:

Immediate-release formulation:

• As an analgesic and Antipyretic.

• Revascularization procedures:

  • CABG,
  • coronary angioplasty
  • carotid endarterectomy.

• Rheumatoid arthritis and other rheumatic diseases:

• To reduce the risk of death in vascular diseases such as:

  • ischemic stroke,
  • The transient ischemic attack,
  • acute myocardial infarction,
  • prevention of recurrent myocardial infarction,
  • unstable angina, and
  • chronic stable angina

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Extended-release capsules:

• Chronic coronary artery disease

• History of ischemic stroke or transient ischemic attack:

  • In situations for which a rapid onset of action is required such as acute treatment of Myocardial infarction or before the percutaneous coronary intervention, immediate-release formulations should be used instead of the extended-release.

• Off Label Use of Aspirin in Adults:

  • Acute coronary syndromes (STEMI, NSTEMI, unstable angina);
  • Acute ischemic stroke and transient ischemic attack;
  • For the prevention of thromboembolism in atrial fibrillation
  • Asymptomatic carotid artery stenosis
  • Primary and secondary prevention of colorectal cancer risk reduction
  • Colorectal cancer risk reduction in hereditary nonpolyposis colon cancer carriers (Lynch syndrome);
  • Percutaneous coronary intervention;
  • Pericarditis;
  • Pericarditis associated with MI;
  • Peripheral arterial disease;
  • Polycythemia vera;
  • Preeclampsia (prevention);
  • Primary prevention of cardiovascular disease;
  • Secondary prevention of cardiovascular disease in patients with diabetes
  • Secondary prevention after CABG surgery;
  • Thromboprophylaxis in prosthetic heart valve replacement
  • Venous thromboembolism extended therapy to prevent recurrence (in patients who have completed anticoagulation treatment and decided to stop oral anticoagulation);
  • Venous thromboembolism (VTE) prophylaxis for total hip (THA) or knee (TKA) arthroplasty

Aspirin Dose in Adults:

Note: Typical maintenance dosing of aspirin is 81 mg once a day is used for most cardiovascular diseases.

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Acute coronary syndrome (ST-elevation myocardial infarction [STEMI], non-ST-elevation acute coronary syndromes [NSTE-ACS]): 

• On presentation 162 to 325 mg is given (patient should chew non-enteric-coated aspirin especially if not taking before the presentation).
  • For patients unable to take orally may use a 600 mg rectal suppository dose.
• 81 to 325 mg once daily continued as a maintenance dose.

• Concomitant antiplatelet therapy:

  • STEMI (ST-elevation myocardial infarction):
    • Aspirin is recommended in combination with either clopidogrel, prasugrel, or ticagrelor given as early as possible or at time of PCI.
    • In addition to dual antiplatelet therapy, parenteral anticoagulant therapy is indicated.
  • Post-PCI stenting, consult clinical practice guidelines.

Analgesic and antipyretic:

• Oral:
  • 325 to 650 mg every 4 hours or
  • 975 mg as needed every 6 hours or
  • 500 to 1,000 mg as needed every 4 to 6 hours for no more than 10 days or as directed by health care provider; (max dose is 4g/day)
• Rectal:
  • 300 to 600 mg every 4 hours for no more than 10 days or as directed by a health care provider

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Aortic valve repair (off-label use):

• 50 to 100 mg once a day.

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Atrial fibrillation (to prevent thromboembolism) (off-label use):

• Primary prevention:
  • Patients at low risk of ischemic stroke (CHADS -VASc score of 1): 75 to 325 mg once a day may be considered.

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Asymptomatic Carotid artery stenosis as off-label use:

• 75 to 100 mg once a day.

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Carotid endarterectomy (off-label dosing):

• 75 to 100 mg once a day.

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Established or chronic Coronary artery disease:

• 75 to 100 mg once daily a day.

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Percutaneous coronary intervention (PCI) (off-label dosing):

Non-emergent PCI:

• Pre-procedure:
  • 81 to 325 mg (325 mg [nonenteric coated] in aspirin-naive patients) starting at least 2 hours (preferably 24 hours) before the procedure.
• Postprocedure:
  • 81 mg once daily continued indefinitely with clopidogrel for at least 14 days up to 12 months.

Primary PCI:

• Preprocedure:
  • 162 to 325 mg as early as possible prior to the procedure; 325 mg preferred.
• Postprocedure:
  • 81 mg once daily continued indefinitely with clopidogrel for at least 14 days up to 12 months.

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Pericarditis (off-label use):

• Initially, 2.4 to 3.6 g daily in 3 to 4 divided doses;
• Then maintenance dose of 3.6 to 5.4 g daily in divided doses;
• gradually taper over a period of  2 to 3 weeks.

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Pericarditis in association with myocardial infarction (off-label use):

• Initially 650 mg 4 times daily;
• may increase after 24 hours to 975 mg 4 times a day if needed.

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Peripheral arterial disease (off-label use):

• 75 to 325 mg once a day.
• After lower extremity revascularization the use in combination with clopidogrel may be considered in patients with symptomatic PAD.

Note: The above can also be used for:

• Intermittent claudication
• critical limb ischemia,
• prior lower extremity revascularization,
• prior amputation for lower extremity ischemia.

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Peripheral artery percutaneous transluminal angioplasty (with or without stenting) or postprocedure peripheral artery bypass graft surgery as off-label use):

• 75 to 100 mg once a day.

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Polycythemia vera (off-label use):

• 75 to 100 mg once a day.

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Preeclampsia prevention in at-risk women (off-label use):

• 75 to 150 mg once a day.

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Primary prevention of cardiovascular disease (off-label use):

• 75 to 162 mg once a day.

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Secondary prevention of cardiovascular disease in patients with diabetes) (off-label use):

• 75 to 162 mg once a day.

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Secondary prevention after coronary artery bypass graft (CABG) surgery (off-label dosing):

• 81 to 325 mg once a day orally, continue indefinitely. Following off-pump CABG, administer 81 to 162 mg with clopidogrel until 12 months.

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Thromboprophylaxis of prosthetic heart valve replacement (off-label use):

• Bioprosthetic aortic or mitral valve:
  • 75 to 100 mg once a day. Anticoagulation with warfarin during the first 3 to 6 months after surgery if needed.
• Mechanical aortic or mitral valve:
  • 75 to 100 mg once a day in combination with warfarin.

Note: May increase the dose to 325mg once a day in patients with ischemic stroke or systemic emboli despite adequate thrombolytic therapy.

• Mechanical or bioprosthetic valves in pregnant women:
  • 75 to 100 mg once a day in the 2nd and 3rd trimester combined with anticoagulation therapy.
• Transcatheter aortic valve replacement (TAVR):
  • 75 to 100 mg once a day in combination with clopidogrel.

Note: Do not use anticoagulation with dual antiplatelets ( like aspirin + clopidogril ) after the procedure.

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Stroke and TIA: 

• Acute ischemic stroke and TIA:
  • 160 to 325 mg within 48 hours of stroke/TIA onset, then 75 to 100 mg once a day.
  • do not administer aspirin within 24 hours after administration of alteplase.
  • Clopidogrel + Aspirin may be given within 24 hrs of a minor ischemic stroke or TIA and continued for 21 days.
• Extended-release capsule for the maintenance dose in secondary prevention:
  • 162.5 mg once daily.

Note: Extended-release capsules should not be used as initial therapy for stroke and TIA. Use immediate release.

• Secondary prevention of cardioembolic stroke when oral anticoagulation are unsuitable (off-label):
  • 75 to 100 mg once a day.

• Cryptogenic with patent foramen ovale (PFO) or atrial septal aneurysm (off-label use):
  • 50 to 100 mg once a day.

• Intracranial atherosclerosis (50% to 99% stenosis of a major intracranial artery):
  • 325 mg once daily (Use in combination with clopidogrel in patients with TIA/Stroke in patients due to severe stenosis i-e 70 to 99%).
• Noncardioembolic, secondary prevention (off-label use):
  • 75 to 325 mg once a day.
• Primary prevention in Women at high risk for the first stroke:
  • 81 mg once a day or 100 mg every other day.

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Venous thromboembolism (VTE), extended therapy to prevent recurrence (in patients who have completed anticoagulation treatment and decided to stop oral anticoagulation) (off-label use):

• 100 mg once a day.

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Venous thromboembolism (VTE) prophylaxis for total hip (THA) or knee (TKA) arthroplasty (off-label use):

• After a 5-day course of postoperative rivaroxaban prophylaxis, initiate aspirin at 81 mg once a day starting on postoperative day 6 and continue for 9 days for TKA (total duration: 14 days) or 30 days for THA (total duration: 35 days).

Note: Use rivaroxaban followed by aspirin.

• Use only in low-risk patients who undergo elective unilateral THA or TKA,
• ambulate within 24 hours after surgery,

DO NOT USE IN PATIENTS who have:

• additional risk factors for VTE,
• indications for long-term anticoagulation,
• lower limb or hip fracture in the previous 3 months,
• expected major surgery in the upcoming 3 months.

Aspirin Dose in Children:

Analgesic:

Not recommended in <18yrs of age for analgesia due to association with reye syndrome.

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Anti-inflammatory: Limited data available:

• Infants, Children, and Adolescents:
  • Orally 60 to 90 mg/kg/day in divided doses initially; and then 80 to 100 mg/kg/day divided every 6 to 8 hours as maintenance dose.
  • Monitor serum concentrations.

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Acute ischemic stroke:

• Noncardioembolic:

  • 1 to 5 mg/kg/dose once a day for ≥2 years.
  • Patients with recurrent acute ischemic stroke or TIAs should be transitioned to clopidogrel, LMWH, or warfarin.

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• Secondary to Moyamoya and non-Moyamoya vasculopathy:

  • 1 to 5 mg/kg/dose once a day.

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• Prosthetic heart valve:

  • Bioprosthetic aortic valve (with normal sinus rhythm):
    • 1 to 5 mg/kg/dose once a day for 3 months.

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• Mechanical aortic and/or mitral valve:

  • 1 to 5 mg/kg/dose once a day combined with warfarin as first-line antithrombotic therapy.
  • Alternative regimens:
    • 6 to 20 mg/kg/dose once a day in combination with dipyridamole.

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• For the primary prophylaxis of Postoperative Blalock-Taussig and Glenn shunt:

  • 1 to 5 mg/kg/dose once a day.

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• For the primary prophylaxis of Postoperative Norwood, Fontan surgery.

  • 1 to 5 mg/kg/dose once a day.

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• Postprocedure prophylaxis in patients with transcatheter Atrial Septal Defect (ASD) or Ventricular Septal Defect (VSD) devices:

  • 1 to 5 mg/kg/dose once a day starting one to several days prior to implantation and continued for at least 6 months.
  • For older children and adolescents, after device closure of ASD, an additional anticoagulant may be given with aspirin for 3 to 6 months, but the aspirin should continue for at least 6 months.

• Ventricular assist device (VAD) placement:

  • 1 to 5 mg/kg/dose once daily initiated within 72 hours of VAD placement.
  • It should be used with heparin (initiated between 8 to 48 hours following implantation) and with or without dipyridamole.

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Kawasaki disease: Limited data available and the optimal dose has not been established.

Note: 

• Use acetaminophen in patients with Kawasaki disease and presenting with influenza or viral illness.
• Aspirin should not be used in such cases. Use an alternate antiplatelet agent suggested for a minimum of 2 weeks if required.

Infants, Children, and Adolescents:

• Acute phase: 
  • Recommended dosing regimens vary. Use in combination with Intravenous immune globulin (within first 10 days of symptom onset) and corticosteroids in some cases.
• High dose:
  • 80 to 100 mg/kg/day divided every 6 hours for up to 14 days until fever resolves for at least 48 to 72 hours.
• Moderate dose:
  • 30 to 50 mg/kg/day divided every 6 hours for up to 14 days until fever resolves for at least 48 to 72 hours.
• low-dose:
  • 3 to 5 mg/kg/day once a dayfor up to 14 days until fever resolves for at least 48 to 72 hours.

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Rheumatic fever: Limited data available:

• Infants, Children, and Adolescents:
  • Start with 100 mg/kg/day divided into 4 to 5 doses, if the patient responds, then may increase dose to 125 mg/kg/day for 2 weeks.
  • Decrease dose to 60 to 70 mg/kg/day in divided doses for an additional 3 to 6 weeks.

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Migratory polyarthritis, with carditis without cardiomegaly or congestive heart failure:

• Start with 100 mg/kg/day in 4 divided doses for 3 to 5 days, and then 75 mg/kg/day in 4 divided doses for 4 weeks

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Carditis and cardiomegaly or congestive heart failure:

• At the beginning of the tapering of the prednisone dose, aspirin should be started at 75 mg/kg/day in 4 divided doses for 6 weeks

Pregnancy Risk Factor: D (full dose in the third trimester), Not formally assigned any category.

• Salicylates can cross the placenta into fetal circulation, according to some studies.
• The following adverse effects have been reported in the fetus: mortality, intrauterine growth delay, salicylate poisonation, bleeding abnormalities and neonatal acidosis.
• Premature closure of the ductus Arteriosus may be caused by aspirin taken close to delivery.
• Anemia, hemorhage, prolonged gestation and prolonged labor are some of the adverse effects that mother may experience.

Note: Women with low-dose preeclampsia may use aspirin to reduce their risk of developing it.

• Preterm births or history of preeclampsia (34 weeks) or preeclampsia that was >=1 before pregnancy.
• Antiphospholipid syndrome during pregnancy (primary or secondary to SLE).
• Prosthetic valves (along with bioprosthetic or mechanical warfarin)

Aspirin use during breastFeeding:

• After maternal aspirin use, breast milk contains salicylic acid.
• Breastfeeding is not recommended for mothers who take more than 1500mg per day or are on long-term aspirin therapy.
• Be on the lookout for any unusual behavior in your infant.

Aspirin Dose in Kidney disease:

• Analgesia or anti-inflammatory uses:
  • Not recommended in patients with CrCl <10 mL/minute.
• Antiplatelet uses:
  • Not recommended in patients with CrCl <10 mL/minute.
  • May be used in low doses (i-e 75 to 162 mg daily) if the benefits outweigh the risks.
• Hemodialysis:
  • Dialyzable.

Dose in Liver disease:

Do not use in severe liver disease.

Side effects of Aspirin:

Adverse effects may be dose related, idiosyncratic, related to individual sensitivity, or allergy.

• Bleeding:

  • Hemorrhage may occur at virtually any site.
  • Risk is dependent on multiple variables including dosage, concurrent use of multiple agents which alter hemostasis, and patient susceptibility.

• Cardiovascular:

  • Cardiac Arrhythmia
  • Edema
  • Hypotension
  • Tachycardia

• Central Nervous System:

  • Agitation
  • Cerebral Edema
  • Coma
  • Confusion
  • Dizziness
  • Fatigue
  • Headache
  • Hyperthermia
  • Insomnia
  • Lethargy
  • Nervousness
  • Reye's Syndrome

• Dermatologic:

  • Skin Rash
  • Urticaria

• Endocrine & Metabolic:

  • Acidosis
  • Dehydration
  • Hyperglycemia
  • Hyperkalemia
  • Hypernatremia (Buffered Forms)
  • Hypoglycemia (Children)

• Gastrointestinal:

  • Gastrointestinal Ulcer
  • Duodenal Ulcer
  • Dyspepsia
  • Epigastric Distress
  • Gastritis
  • Gastrointestinal Erosion
  • Heartburn
  • Nausea
  • Stomach Pain
  • Vomiting

• Genitourinary:

  • Postpartum Hemorrhage
  • Prolonged Gestation
  • Prolonged Labor
  • Proteinuria
  • Stillborn Infant

• Hematologic & Oncologic:

  • Anemia
  • Blood Coagulation Disorder
  • Disseminated Intravascular Coagulation
  • Hemolytic Anemia
  • Hemorrhage
  • Iron Deficiency Anemia
  • Prolonged Prothrombin Time
  • Thrombocytopenia

• Hepatic:

  • Hepatitis (Reversible)
  • Hepatotoxicity
  • Increased Serum Transaminases

• Hypersensitivity:

  • Anaphylaxis
  • Angioedema

• Neuromuscular & Skeletal:

  • Acetabular Bone Destruction
  • Rhabdomyolysis
  • Weakness

• Otic:

  • Hearing Loss
  • Tinnitus

• Renal:

  • Increased Blood Urea Nitrogen
  • Increased Serum Creatinine
  • Interstitial Nephritis
  • Renal Failure (Including Cases Caused By Rhabdomyolysis)
  • Renal Insufficiency
  • Renal Papillary Necrosis

• Respiratory:

  • Asthma
  • Bronchospasm
  • Dyspnea
  • Hyperventilation
  • Laryngeal Edema
  • Noncardiogenic Pulmonary Edema
  • Respiratory Alkalosis
  • Tachypnea

• Miscellaneous:

  • Low birth weight

Contraindication to Aspirin:

• Hypersensitivity to NSAIDs
• Patients with:
  • Asthma
  • Rhinitis is a condition that affects the nose.
  • Nasal polyps
  • Use in children and teens to prevent viral infections
  • Limited data are available on cross-reactivity of salicylates.

Warnings and Precautions

• Sensitivity to salicylates:
  • Patients with asthma, nasal polyps and sensitive to tartrazine dyes could be at greater risk for salicylate sensitivity.
• Tinnitus
  • If you have tinnitus, or hearing loss, discontinue use.
• Upper gastrointestinal events (e.g. symptomatic and complicated ulcers)
  • Low-dose aspirin can cause an increase of 2 to 4 in upper gastrointestinal events.
  • Aspirin dosage increases, so it is important to avoid overdosing.
• Bleeding disorders:
  • Patients suffering from bleeding disorders should be cautious.
• Dehydration
  • Patients with severe dehydration should be treated with caution.
• Use of ethanol:
  • Drinking excessive amounts of ethanol (>3 drinks/day), can increase bleeding risk and cause gastric mucosal injury.
• Gastrointestinal Disease:
  • Patients with erosive gastritis should be treated with caution. Patients with active pepticul disease should be avoided.
• Hepatic impairment
  • Do not use if you have severe hepatic impairment.
• Renal impairment
  • When using high dosages (e.g, analgesic or anti-inflammatory uses), use with caution and monitor renal function or consider the use of an alternative analgesic/anti-inflammatory agent.
  • Patients with renal impairment may safely take low-dose aspirin (75-162 mg once per day).

Aspirin: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use  

Risk Factor C (Monitor therapy).
Antiplatelet Agents (e.g. P2Y12 inhibitors NSAIDs, SSRIs etc.)	Salicylates may have an adverse or toxic effect that can be increased. This could lead to an increase in bleeding risk.
Antiplatelet Agents (e.g. P2Y12 inhibitors NSAIDs, SSRIs etc.)	May increase the antiplatelet effects of other Agents with Antiplatelet Properties.
Ajmaline	Salicylates can increase the toxic/adverse effects of Ajmaline. Particularly, there may be an increase in the risk of cholestasis.
Alendronate	Alendronate may have an adverse/toxic effect that can be increased by taking aspirin. In particular, Alendronate may increase the risk of adverse events in the upper gastrointestinal tract.
Ammonium Chloride	Salicylates may increase serum concentrations
Angiotensin-Converting Enzyme Inhibitors	Salicylates may enhance the nephrotoxic effect of Angiotensin-Converting Enzyme Inhibitors. Salicylates may diminish the therapeutic effect of Angiotensin-Converting Enzyme Inhibitors.
Anticoagulants	Anticoagulant agents may have antiplatelet properties that can enhance their effectiveness.
Anticoagulants	Salicylates can increase the anticoagulant effects of Anticoagulants.
Benzbromarone	Salicylates can reduce the therapeutic effects of Benzbromarone.
Blood Glucose-Limiting Agents	Salicylates can increase the hypoglycemic effects of Blood Glucose Lowing Agents.
Calcium Channel Blockers (Nondihydropyridine)	May increase the antiplatelet effects of Aspirin.
Carisoprodol	Aspirin can increase serum levels of Carisoprodol's active metabolite(s). Meprobamate concentrations could be increased. The serum concentrations of Carisoprodol may be decreased by taking aspirin.
Cephalothin	Antiplatelet agents may increase the toxic/adverse effects of Cephalothin. In particular, bleeding risk may be increased.
Collagenase (Systemic)	Antiplatelet agents may increase the toxic/adverse effect of Collagenase Systemic. In particular, there may be an increase in the risk of bleeding and/or bruising at the injection site.
Corticosteroids (Systemic)	Salicylates can increase the toxic/adverse effect of Systemic Corticosteroids (Systemic). These include bleeding and gastrointestinal ulceration. Systemic corticosteroids may cause a decrease in serum Salicylates. Salicylate toxicities can occur when corticosteroids are stopped.
Dasatinib	Agents with Antiplatelet Properties may increase the anticoagulant effects. Management: The drug interactions monographs for drugs listed as an exception to this monograph provide more information.
Deoxycholic Acid	Antiplatelet agents may increase the toxic/adverse effects of Deoxycholic Acid. In particular, bleeding and bruising may increase in the treatment area.
Fat Emulsion (Fish oil-based)	Agents with Antiplatelet Property may have an adverse/toxic effect.
Felbinac	May increase the toxic/adverse effects of Aspirin.
Glucosamine	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Heparin	Heparin's anticoagulant effects may be enhanced by aspirin.
Ibritumomab Tiuxetan	Antiplatelet agents may increase the toxic/adverse effects of Ibritumomab Tiuxetan. Both agents can cause impaired platelet function, which could lead to increased bleeding risk.
Ibrutinib	May increase the toxic/adverse effects of agents with Antiplatelet Property.
Inotersen	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Lesinurad	Lesinurad's therapeutic effects may be diminished by taking aspirin.
Limaprost	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Loop Diuretics	Loop Diuretics may be affected by Salicylates. The serum concentrations of Salicylates may be increased by Loop Diuretics.
Multivitamins/Fluoride (with ADE)	May increase the antiplatelet effects of Aspirin. Aspirin may decrease the serum concentration of Multivitamins/Fluoride (with ADE). Aspirin can decrease ascorbic acid absorption.
Multivitamins/Minerals (with ADEK, Folate, Iron)	Aspirin may have an increased antiplatelet effect. Aspirin may decrease the serum concentration of Multivitamins/Minerals (with ADEK, Folate, Iron). Aspirin can decrease the absorption of ascorbic acids.
Multivitamins/Minerals (with AE, No Iron)	Aspirin may have an increased antiplatelet effect. Aspirin may decrease the serum concentration of Multivitamins/Minerals (with AE, No Iron). Aspirin can decrease ascorbic acid absorption.
Nicorandil	Aspirin can increase the toxic/adverse effects of Nicorandil. In particular, there may be an increase in the risk of hemorhage and gastrointestinal ulceration.
Obinutuzumab	Antiplatelet agents may increase the toxic/adverse effects of Obinutuzumab. In particular, there may be an increase in the risk of bleeding-related complications.
Omega-3 Fatty Acids	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Pentosan Polysulfate Sodium	Agents with Antiplatelet Property may have an adverse/toxic effect. Concurrent use of these agents may increase the risk of bleeding.
Pentoxifylline	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Potassium Phosphate	Salicylates may increase serum concentrations
Probenecid	Probenecid's therapeutic effects may be diminished by salicylates
Prostacyclin Analogues	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Salicylates	Antiplatelet agents may increase the toxic/adverse effects of Salicylates. This could lead to an increase in bleeding risk.
Salicylates	Other Salicylates may have an enhanced anticoagulant effect.
Selective Serotonin Reuptake inhibitors	May increase the antiplatelet effects of Aspirin.
Serotonin/Norepinephrine Reuptake Inhibitors	May increase the antiplatelet effects of Aspirin.
Spironolactone	Spironolactone's therapeutic effects may be diminished by aspirin.
Thiopental	Aspirin can decrease Thiopental's protein binding.
Thrombolytic Agents	Agents with Antiplatelet Properties can enhance the anticoagulant effects of Thrombolytic Agents.
Thrombolytic Agents	Salicylates can increase the toxic/adverse effects of Thrombolytic agents. There may be an increased risk of bleeding.
Tiludronate	Tiludronate serum concentrations may be decreased by taking aspirin
Tipranavir	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Tricyclic Antidepressants (Tertiary Amine).	May increase the antiplatelet effects of Aspirin.
Valproate Products	Salicylates can increase serum concentrations of Valproate Products.
Vitamin E (Systemic)	Agents with Antiplatelet Properties may increase the antiplatelet effects.
Risk Factor D (Alternative therapy)
Alcohol (Ethyl)	May increase the toxic/adverse effects of Aspirin. Aspirin's bleeding risk may be increased by drinking alcohol. Aspirin's therapeutic effects may be diminished by alcohol (Ethyl). Alcohol may also interfere with extended-release aspirin's controlled release mechanism. Monitoring: Patients who consume 3 or more alcoholic beverages per day should be monitored for increased bleeding when taking aspirin. Patients should be notified about the possibility of bleeding. Extended release aspirin should be taken 2 hours prior to or 1 hour after alcohol consumption.
Apixaban	Apixaban's toxic/adverse effects may be increased by taking aspirin. The risk of bleeding could be increased. Management: Take the time to carefully consider both the risks and the benefits of this combination, and keep an eye on it.
Inhibitors of carbonic anhydrase	Salicylates can increase the toxic/adverse effect of Carbonic Anhydrase Inhibitors. This combination could increase salicylate toxicities. Management: Avoid these combinations when possible.Dichlorphenamide use with high-dose aspirin as contraindicated. Monitor patients carefully for any adverse effects if another combination is used. Tachypnea and anorexia have all been reported. Exceptions: Brinzolamide; Dorzolamide.
Dabigatran Etexilate	Aspirin can increase the toxic/adverse effects of Dabigatran Etexilate. The risk of bleeding is increased by using this combination. Management: Be aware of the risks and benefits and keep an eye on your health. Canadian labeling suggests that low doses of aspirin may be used, but antiplatelets should not be used to prevent strokes in patients with atrial fibrillation.
Edoxaban	Edoxaban's toxic/adverse effects may be increased by taking aspirin. In particular, bleeding risk may increase. Edoxaban serum concentration may be increased by taking aspirin. Take into consideration the potential risks and benefits. In combination, it is recommended to increase monitoring for bleeding.
Ginkgo Biloba	Salicylates may have an increased anticoagulant activity. Management: You may consider other combinations of these agents. If salicylates are combined with ginkgo biloba, be sure to monitor for bleeding signs and symptoms.
Herbs (Anticoagulant/Antiplatelet Properties) (eg, Alfalfa, Anise, Bilberry)	Agents with Antiplatelet Property may have an adverse/toxic effect. Possible bleeding. Management: Avoid using combination medications whenever possible. Monitor for bleeding signs if you use this combination. Stop using herbal products that contain anticoagulant or Antiplatelet actions two weeks before any surgical, dental or invasive procedure.
Herbs (Anticoagulant/Antiplatelet Properties) (eg, Alfalfa, Anise, Bilberry)	Salicylates may have an adverse/toxic effect that can be increased. Possible bleeding.
Hyaluronidase	Salicylates can decrease the therapeutic effects of Hyaluronidase. Management: Patients who are given salicylates, especially at higher doses, may not have the desired clinical response to standard doses hyaluronidase. Higher doses of Hyaluronidase might be necessary.
Methotrexate	Methotrexate serum concentrations could be increased by salicylates. Not likely to be of concern are salicylate doses that are used for the prevention of heart attacks.
Nonsteroidal Anti-Inflammatory Agents COX-2 Selective	Aspirin can increase the toxic/adverse effects of Nonsteroidal Anti-Inflammatory agents (COX-2 Selective). Management: It is not recommended to use aspirin in combination with cardioprotective doses. Concurrent use of low-dose aspirin and a COX-2 inhibitor with aspirin is allowed, but patients should be closely monitored for signs/symptoms such as GI ulceration/bleeding.
Nonsteroidal Anti-Inflammatory Drugs (Nonselective).	Salicylates may have an adverse/toxic effect that can be increased. This combination may increase the risk of bleeding. The cardioprotective effects of Salicylates may be diminished by Nonsteroidal Anti-Inflammatory Agents. Salicylates can decrease serum Nonsteroidal AntiInflammatory Agents' (Nonselective) concentrations.
PRALAtrexate	Salicylates can increase serum PRALAtrexate concentrations. It is unlikely that salicylates used to prophylaxis cardiovascular events will cause concern.
Rivaroxaban	Rivaroxaban's toxic/adverse effects may be increased by aspirin. The risk of bleeding could be increased. Management: Take into consideration the risks and benefits and keep an eye on it.
Sincalide	Sincalide may be less effective if drugs that affect gallbladder function are taken. Management: Before Sincalide is used to stimulate the gallbladder, discontinue any drugs that affect gallbladder motility.
Sucroferric Oxyhydroxide	It may cause a decrease in serum Aspirin concentration. Administration: Take aspirin at the very least one hour before you take sucroferric Oxyhydroxide.
Talniflumate	Talniflumate's toxic/adverse effects may be exacerbated by Aspirin. Management: If possible, look for alternatives to this combination. It is not recommended to use concurrently.
Ticagrelor	Ticagrelor's antiplatelet effects may be enhanced by aspirin. Ticagrelor's therapeutic effects may be diminished by aspirin. Adult patients who take ticagrelor daily may experience a decrease in the effectiveness of clopidogrel. Adults taking ticagrelor should not take more than 100mg of aspirin daily. Canadian guidelines recommend that adults not take aspirin daily in excess of 150 mg.
Varicella Virus-Containing Vaccines	Salicylates can increase the toxic/adverse effects of Varicella Virus-Containing Vaccines. Reye's Syndrome could develop.
Vitamin K antagonists (eg warfarin)	Vitamin K Antagonists might have an anticoagulant effect that is enhanced by salicylates.
Risk Factor X (Avoid Combination)
Dexibuprofen	Aspirin can increase the toxic/adverse effects of Dexibuprofen. Aspirin's cardioprotective effects may be diminished by Dexibuprofen.
Dexketoprofen	Salicylates can increase the toxic/adverse effects of Dexketoprofen. Dexketoprofen can decrease the therapeutic effects of Salicylates. Salicylates can decrease serum Dexketoprofen concentrations. Management: High-dose salicylates (more than 3 g/day in adults) should not be used in conjunction with dexketoprofen. To minimize interactions, dexketoprofen should be administered between 30-120 minutes and 8 hours before aspirin cardioprotective doses.
Floctafenine	This combination may increase the toxic/adverse effects of Aspirin. This combination may increase the risk of bleeding. Aspirin's cardioprotective effects may be diminished by Floctafenine.
Influenza Virus Vaccine (Live/Attenuated)	Salicylates may have an adverse/toxic effect that can be increased. Reye's syndrome, in particular, may occur.
Ketorolac, (Nasal).	This combination may increase the toxic/adverse effects of Aspirin. This combination may increase the risk of bleeding. Aspirin's cardioprotective effects may be diminished by Ketorolac (Nasal).
Ketorolac Systemic	This combination may increase the toxic/adverse effects of Aspirin. This combination may increase the risk of bleeding. Ketorolac (Systemic), may decrease the cardioprotective effects of Aspirin.
Macimorelin	Aspirin can reduce the diagnostic power of Macimorelin.
Omacetaxine	Omacetaxine may have an adverse/toxic effect that can be increased by aspirin. In particular, bleeding-related events can be more common with Omacetaxine. Patients with a lower platelet count than 50,000/uL should not use aspirin and omacetaxine together.
Sulfinpyrazone	Salicylates can lower the serum concentrations of Sulfinpyrazone.
Urokinase	Agents with Antiplatelet Property may increase the anticoagulant effects of Urokinase.

Monitor:

• Platelet dysfunction in patients with bleeding diathesis like thrombocytopenia, liver, and renal functions.
• Tinnitus and cinchonism
• Renal functions
• Liver functions

How to take Aspirin?

Oral:

• Immediate-release tablets:
  • Do not crush the enteric-coated tablet.
  • should be taken with food or a full glass of water to minimize GI distress.
  • In situations for which a rapid onset of action is required (e.g., acute treatment of myocardial infarction), have patient chew immediate-release tablet.

    ---

• Extended-release capsules:
  • Do not cut, crush, or chew.
  • Administer with a full glass of water at the same time each day.
  • Not to be administered 2 hours before or 1 hour after alcohol consumption.

    ---

Rectal:

• Remove suppository from the plastic packet and insert into the rectum as far as possible.

Mechanism of action of Aspirin:

• It acts by inhibiting irreversibly cyclooxygenase-1 (COX-1) enzymes via acetylation.
• This results in decreased prostaglandin formation and thromboxane precursors. It has antipyretic, analgesic, and anti-inflammatory properties.

Initial: Instant release: Platelet inhibition within 1 hour (nonenteric coated). It is possible that enteric-coated might be delayed.

Notice:Both enteric-coated and non-enteric-coated tablets can inhibit platelet aggregation in 20 minutes. It is recommended that you chew the tablets if you need a quick effect.

Duration:

• Immediate-release: 4 to 6 hours; however, platelet inhibitory effects last the lifetime of the platelet (~10 days) due to its irreversible inhibition of platelet COX-1.

Absorption:

• Immediate-release: Rapidly absorbed
• Extended-release capsule: dependent upon food, alcohol, and gastric pH.

It is readily distributed into most body fluids and tissues; hydrolyzed to the active salicylate by esterases in the gastrointestinal mucosa, red blood cells, synovial fluid and blood

Protein binding: ~90% to 94% (to albumin).

Metabolism:

• Hydrolyzed to salicylate (active) by esterases in GI mucosa, red blood cells, synovial fluid, and blood;
• metabolism of salicylate occurs primarily by hepatic conjugation; metabolic pathways are saturable.

Bioavailability: Immediate release: 50% to 75%.

Half-life elimination:

• Parent drug: Plasma concentration: 15 to 20 minutes;
• Salicylates (dose-dependent):
  • 3 hours at lower doses (300 to 600 mg),
  • 5 to 6 hours (after 1 g),
  • 10 hours with higher doses

Time to peak serum concentration:

• • Immediate release: ~1 to 2 hours (nonenteric-coated), 3 to 4 hours (entericcoated).
  • Extended-release capsule: ~2 hours.

Excretion: Urine (75% as salicyluric acid, 10% as salicylic acid)

International Brand Names of Aspirin:

• Ascriptin Maximum Strength
• Ascriptin Regular Strength
• Aspercin
• Aspir-low
• Aspirin Adult Low Strength
• Aspirin EC Low Strength
• Bayer Aspirin EC Low Dose
• Bayer Aspirin Extra Strength
• Bayer Aspirin
• Regimen Adult Low Strength
• Bayer Aspirin Regimen Children's
• Bayer Aspirin Regimen
• Regular Strength
• Bayer Genuine Aspirin
• Bayer Plus Extra Strength
• Bayer Women's
• Low Dose Aspirin
• Buffasal
• Bufferin Extra Strength
• Bufferin
• Buffinol
• Ecotrin Low Strength
• Ecotrin
• Halfprin
• St Joseph Adult Aspirin
• Tri-Buffered Aspirin
• AAS
• Acard
• Aceprin
• Acetard
• Aceticil
• Acetysal
• Acitab
• Adiprin EC
• Adiro
• Albyl-E
• Alexoprine
• Algina
• Andol
• Ansin
• Antacsal-E
• Anthrom
• Aptor
• Artebin
• Asactal
• Asam
• Asawin
• Ascardia
• ASP
• Aspa
• Aspec
• Aspen
• Aspenorm
• Aspent
• Aspeter
• Aspicard
• Aspico
• Aspicot
• Aspilets
• Aspilets EC
• Aspimed
• Aspin
• Aspinal
• Aspirax
• Aspire
• Aspirin
• Aspirin Bayer
• Aspirin Cardio
• Aspirina
• Aspirina efervescente
• Aspirina Junior
• Aspitor
• Aspro
• Aspro Junior
• Asrina
• ASS
• Asthromed
• Astrix
• B-Aspirin
• Bamyl
• Bayaspirin Protect 100
• Bayaspirina
• Bayer Aspirin Cardio
• Bayprin EC
• Bokey
• Bufferin
• Cafemol Childrens Size
• Caprin
• Cardiomagnyl
• Cardioprin
• Cardioprin 100
• Cardioton
• Cartia
• Caspirin
• Circlevein
• Colfarit
• Comoprin
• Cortal
• Dispril
• Disprin
• Ecasil
• Ecorin
• Ecosprin
• Ecotrin
• Encine EM
• Eskotrin
• Frosit
• Globentyl
• Glocar
• Godamed
• Jusprin
• Kardegic
• Kidiprin
• Lodosprin
• Lopirin
• Magnecyl
• Melabon
• Miniaspi 80
• Naspro
• Neospin
• Norspirinal
• Novasen
• Nu-Seals
• Nuasa
• Nuprin
• Plaquetasa
• Remin
• Rhonal
• Salisal
• Salisalido
• Salospir
• Sedergine
• Tevapirin
• Thomapyrin
• Thrombo-Aspilets
• Tromcor
• V-AS

Aspirin Brand Names in Pakistan:

Aspirin 75 mg Tablets in Pakistan
Anaprin	Opal Laboratories (Pvt) Ltd.
Angipro	Unimark Pharmaceuticals
Anticlot	Euro Pharma International
Apiscot	Scotmann Pharmaceuticals
Asa	Don Valley Pharmaceuticals (Pvt) Ltd.
Ascard	Atco Laboratories Limited
Askprin	Askari Pharmaceuticals.
Aspisafe	Zafa Pharmaceutical Laboratories (Pvt) Ltd.
Aspiwan	Nawan Laboratories (Pvt) Ltd.
Asrin	Star Laboratories (Pvt) Ltd.
Caprin Ec	Candid Pharmaceuticals
Cv-75	Wilsons Pharmaceuticals
Doloprin-75	Pacific Pharmaceuticals Ltd.
Ecotrin	Wilshire Laboratories (Pvt) Ltd.
Erocid	Eros Pharmaceuticals
Glorin	Global Pharmaceuticals
Jeprin	Genome Pharmaceuticals (Pvt) Ltd
Loprin	Highnoon Laboratories Ltd.
Masprin	Mass Pharma (Private) Limited
Mini Prin	Bloom Pharmaceuticals (Pvt) Ltd.
Orsprine	Orta Labs. (Pvt) Ltd.
Prosperin	Epoch Pharmaceutical
Rescard	Rasco Pharma
Vin	Saydon Pharmaceutical Industries (Pvt) Ltd.

Aspirin 100 Mg Tablets in Pakistan
Disprin-Cv	Reckitt Benckiser Pakistan Ltd.

Aspirin 150 Mg Tablets in Pakistan
Anaprin	Opal Laboratories (Pvt) Ltd.
Apiscot	Scotmann Pharmaceuticals
Asa	Don Valley Pharmaceuticals (Pvt) Ltd.
Ascard	Atco Laboratories Limited
Askprin	Askari Pharmaceuticals.
Aspisafe	Zafa Pharmaceutical Laboratories (Pvt) Ltd.
Asrin	Star Laboratories (Pvt) Ltd.
Caprin Ec	Candid Pharmaceuticals
Cv- 150	Wilsons Pharmaceuticals
Glorin	Global Pharmaceuticals
Loprin	Highnoon Laboratories Ltd.
Masprin	Mass Pharma (Private) Limited
Prosperin	Epoch Pharmaceutical
Vin	Saydon Pharmaceutical Industries (Pvt) Ltd.

Aspirin 300 Mg Tablets in Pakistan
Adalgin	Adamjee Pharmaceuticals (Pvt) Ltd.
Apecirin	Alfalah Pharma (Pvt) Ltd.
Ascamol	Eros Pharmaceuticals
Ascamol	Eros Pharmaceuticals
Aspirin Comp	Nawabsons Laboratories (Pvt) Ltd.
Aspirin Compound	Ideal Pharmaceutical Industries
Dard Aram	Lisko Pakistan (Pvt) Ltd
Disprin	Reckitt Benckiser Pakistan Ltd.
Disprin Cold "N" Fever	Reckitt Benckiser Pakistan Ltd.
Donamol Plus	Rakaposhi Pharmaceutical (Pvt) Ltd.
Empirin Comp	Glaxosmithkline
Febrinol Comp	Pharmawise Labs. (Pvt) Ltd.
Iodopyrin	Ideal Pharmaceutical Industries
Kanaprin	Krka-Pak Pharmaceutical & Chemical Works
Kaprin Compound	Karachi Pharmaceutical Laboratory
Liskoprin	Lisko Pakistan (Pvt) Ltd
Mediprin	Medicaids Pakistan (Pvt) Ltd.
Mepol	Reko Pharmacal (Pvt) Ltd.
Meprogesic	Medicaids Pakistan (Pvt) Ltd.
Nopain	Schazoo Zaka
Pabfin	Drug Pharm (Pvt) Ltd.
Panam Plus	English Pharmaceuticals Industries
Panarin	Pharmacare Laboratories (Pvt) Ltd.
Panogesic	Davis Pharmaceutical Laboratories
Paracetamol Compound	Progressive Laboratories
Paracetamol Compound	Unexo Labs (Pvt) Ltd.
Paracetamol Compounds	Ardin Pharmaceuticals
Paxfin	Star Laboratories (Pvt) Ltd.
Sarapyrine	Wilshire Laboratories (Pvt) Ltd.
Schazopyrin	The Schazoo Laboratories Ltd.
Semopyrin	Semos Pharmaceuticals (Pvt) Ltd.
Synopar	Synchro Pharmaceuticals
Trigesic	Wilshire Laboratories (Pvt) Ltd.
Zepyrine	Xenon Pharmaceuticals (Pvt) Ltd.

Aspirin 500 Mg Tablets in Pakistan
Disprin Max	Reckitt Benckiser Pakistan Ltd.