Aspirin Indications, Contraindications, Warning

Aspirin is a common medicine that has a number of uses, from relieving pain? to reducing the risk of serious problems such as heart attacks and strokes.

Mechanism of Action of Aspirin

Aspirin acetylates prostaglandin endoperoxide synthase (prostaglandin G/H-synthase) and irreversibly inhibits its cyclooxygenase (COX) activity. The enzyme catalyzes the conversion of arachidonic acid to PGH2, the first committed step in prostanoid biosynthesis. Two isoforms of prostaglandin endoperoxide synthase exist, PGHS-1 and PGHS-2 (also referred to as COX-1 and COX-2, respectively). PGHS-1 (COX-1) is expressed constitutively in most cell types, including platelets. PGHS-2 (COX-2) is undetectable in most mammalian cells, but its expression can be induced rapidly in response to mitogenic and inflammatory stimuli. Aspirin is a relatively selective inhibitor of platelet? PGHS-1 (cyclooxygenase-1, COX-1). The existence of 2 isoenzymes with different aspirin sensitivities, coupled with extremely different recovery rates of their cyclooxygenase (COX) activity following inactivation by aspirin, at least partially explains the different dosage requirements and durations of aspirin effects on platelet function versus the drug’s analgesic? and infection?, or irritation, often causing pain, swelling?, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation?, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।" data-rx-term="anti-inflammatory" data-rx-definition="Anti-inflammatory means reducing inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।">anti-inflammatory? effects. Human platelets and vascular endothelial cells process PGH2 to produce thromboxane A2 and prostacyclin (epoprostenol, PGI2), respectively. Thromboxane A2 induces platelet aggregation and vasoconstriction, while prostacyclin inhibits platelet aggregation and induces vasodilation. Aspirin is antithrombotic in a wide range of doses inhibiting thromboxane A2and prostacyclin.

Aspirin Indications

At high doses – usually 300mg – aspirin can relieve pain, reduce a high temperature (fever) and reduce swelling.

• For use in the temporary relief of various forms of pain, inflammation associated with various conditions (including rheumatoid arthritis, juvenile rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, and ankylosing spondylitis), and is also used to reduce the risk of death and/or nonfatal myocardial infarction in patients with a previous infarction or unstable angina pectoris.
• Treatment of polycythemia vera
• Headaches and migraines
• A toothache
• Period pains
• General aches and pains
• a heart attack or angina
• a stroke or transient ischemic attack 
• peripheral arterial disease
• coronary artery bypass surgery or another operation on your heart or blood vessels
• Secondary prevention of myocardial infarction.
• Prevention of cardiovascular morbidity in patients suffering from stable angina pectoris.
• History of unstable angina pectoris, except during the acute phase.
• Prevention of graft occlusion after Coronary Artery Bypass Grafting (CABG).
• Coronary angioplasty, except during the acute phase.
• Secondary prevention of transient ischaemic attacks (TIA) and ischaemic cerebrovascular accidents (CVA), provided intracerebral hemorrhages have been ruled out.
• Acute Myocardial infarction
• Aspirin may also be prescribed for children after heart surgery or to treat Kawasaki disease. But it shouldn’t be given to anyone under 16 years old without medical supervision.

Therapeutic Indications of Aspirin

• Anti-Inflammatory Agents, Non-Steroidal; Cyclooxygenase Inhibitors; Fibrinolytic
• Low doses of aspirin (<100 mg daily) are used widely for their cardioprotective effects.
• Salicylates are indicated to relieve myalgia, musculoskeletal pain, and other symptoms of nonrheumatic inflammatory conditions such as athletic injuries, bursitis, capsulitis, tendinitis, and nonspecific acute tenosynovitis.
• Salicylates are indicated for the symptomatic relief of acute and chronic rheumatoid arthritis, juvenile arthritis, osteoarthritis, and related rheumatic diseases. Aspirin is usually the first agent to be used and may be the drug of choice in patients able to tolerate prolonged therapy with high doses.
• These agents do not affect the progressive course of rheumatoid arthritis. Concurrent treatment with a glucocorticoid or a disease-modifying antirheumatic agent may be needed, depending on the condition being treated and patient response.
• Salicylates are also used to reduce arthritic complications associated with systemic lupus erythematosus.
• Salicylates are indicated to reduce fever and inflammation in rheumatic fever. However, they do not prevent cardiac or other complications associated with this condition.
• Sodium salicylate should be avoided in rheumatic fever if congestive cardiac complications are present because of its sodium content. Also, large doses of any salicylate should be avoided in rheumatic fever if severe carditis is present because of possible adverse cardiovascular effects.
• Aspirin is indicated in the treatment of men who have had transient brain ischemia due to fibrin platelet emboli to reduce the recurrence of transient ischemic attacks and the risk of stroke and death.
• Aspirin is also used in the treatment of women with transient brain ischemia due to fibrin platelet emboli. However, its efficacy in preventing stroke and death in female patients has not been established.
• Aspirin is also indicated in the treatment of patients with documented, unexplained transient ischemic attacks associated with mitral valve prolapse. However, if transient ischemic attacks continue to occur after an adequate trial of aspirin therapy, aspirin should be discontinued and an oral anticoagulant administered instead.
• Aspirin is also indicated to prevent initial or recurrent cerebrovascular embolism, transient ischemic attacks, and stroke following carotid endarterectomy. Aspirin is indicated in the treatment of patients who have had a completed thrombotic stroke, to prevent a recurrence.
• Aspirin is indicated for its anti-inflammatory, antipyretic, and antithrombotic effects in the treatment of Kawasaki disease (Kawasaki syndrome, mucocutaneous lymph node syndrome) in children.
• It reduces fever, relieves inflammation (e.g., lymphadenitis, mucositis, conjunctivitis, serositis), and may reduce the occurrence of cardiovascular complications. However, the combination of high-dose intravenous gamma globulin and aspirin has been shown to be more effective than aspirin alone in reducing the formation of coronary artery abnormalities.
• Thrombotic thrombocytopenic purpura is a severe multisystemic disorder of unknown origin. The association of relapsing thrombotic thrombocytopenic purpura with pregnancy is rare but well documented and high mortality rates of mothers and fetuses have been reported so far.
• Since the introduction of plasma therapy for treating the acute exacerbations of the disease, overall mortality rates have decreased significantly. It is now evident that the manifestations of the disease may reappear even after long disease-free intervals and as many as a thirds of the recovering patients may develop a relapse.
• Presented are two thrombotic thrombocytopenic purpura patients with relapsing thrombotic thrombocytopenic purpura complicating their pregnancies. Prophylactic treatment with aspirin and dipyridamole during their last three successful pregnancies prevented or minimized the severity of thrombotic thrombocytopenic purpura relapses.

Contra-Indications of Aspirin

Most people can take aspirin safely. But you should get advice from a pharmacist or doctor before taking it if you:

• Asthma
• Frequent stuffed or runny nose
• Nasal polyps (growths on the linings of the nose)
• Anemia
• Gout
• Diabetes
• Liver or kidney disease
• Hemophilia (a bleeding disorder) or any other bleeding conditions
• have had an allergic reaction to aspirin or non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, in the past
• have asthma
• have had stomach ulcers in the past
• have severe liver or kidney problems
• have haemophilia or another bleeding disorder
• have uncontrolled high blood pressure
• are looking for medication for a child under 16 – medication containing aspirin shouldn’t be given to children under 16

Dosage of Aspirin

Strengths:  75 mg, 150 mg, 300 mg 500 mg; 600 mg , 800 mg

Myocardial Infarction

Immediate-Release

• Initial dose: 160 to 162.5 mg orally once as soon as myocardial infarction is suspected
• Maintenance dose: 160 to 162.5 mg orally once a day for 30 days post-infarction

Fever

Oral

• 300 to 650 mg orally every 4 to 6 hours as needed
• Maximum dose: 4 g in 24 hours

Rectal

• 300 to 600 mg rectally every 4 hours

Ischemic Stroke

• Immediate-release: 50 to 325 mg orally once a day
• Extended-release (ER): 162.5 mg orally once a day

Ischemic Stroke – Prophylaxis

• Immediate-release: 50 to 325 mg orally once a day
• Extended-release (ER): 162.5 mg orally once a day

Angina Pectoris Prophylaxis

• Immediate-release (IR): 75 mg to 325 mg orally once a day
• Extended-release (ER): 162 mg orally once a day

Angina Pectoris

• Immediate-release (IR): 75 mg to 325 mg orally once a day
• Extended-release (ER): 162 mg orally once a day

Side Effects of Aspirin

The most common

• Abdominal or stomach cramping, burning, or tenderness
• Upper respiratory tract infection
• Chest pain
• Headache
• Joint painPain
• Dizziness
• Nausea and vomiting
• Severe stomach ache
• epigastric pain,
• diarrhoea,
• anorexia,
• flatulence,
• headache,
• dizziness,
•  fainting, fast or pounding heartbeats;

More common

• Chest pain
• collection of blood under the skin
• Severe stomach ache
• Severe diarrhea
• Mouth sores
• Vaginal thrush
• Skin rash
• Headache
• Ringing or buzzing in the ears
• Decreased appetite
• deep, dark purple bruise
• itching, pain, redness, or swelling
• pain in general
• red or purple spots on the skin, varying in size from pinpoint to large bruises
• Loss of hearing
• Swelling of the eyes, face, lips, tongue, or throat
• Wheezing or breathing difficulties
• Fast heartbeat or fast breathing
• Bloody vomit or vomit that looks like coffee grounds
• Bright red blood in stools or black or tarry stools

Less common

• Nosebleed
• painful or difficult urination
• shortness of breath
• vomiting of blood or material that looks like coffee grounds
• Black, tarry stools
• blistering, flaking, or peeling of the skin
• blood in the urine or stools
• confusion
• fever, chills, or sore throat
• headache (sudden, severe)
• nausea or vomiting
• stomach pain (severe)
• ulcers, sores, or white spots in the mouth
• unusual bleeding or bruising

Drug Interactions of Aspirin

Aspirin may interact with following drugs, supplements & may decrease the efficacy of the drug

• antacids (e.g., aluminum hydroxide, calcium carbonate, magnesium hydroxide)
• “azole” antifungals (e.g., fluconazole, ketoconazole, voriconazole)
• bortezomib
• bupropion
• calcium channel blockers (e.g., amlodipine, diltiazem, nifedipine, verapamil)
• cimetidine
• dasatinib
• glucosamine
• heparin
• loop diuretics  furosemide
• methotrexate
• multivitamin/mineral supplements
• omega-3 fatty acids
• pentoxifylline
• low molecular weight heparins
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• nonsteroidal anti-inflammatories (NSAIDs; e.g., ibuprofen, diclofenac, ketorolac,naproxen)
• proton pump inhibitors (PPIs; e.g., esomeprazole, lansoprazole, omeprazole, pantoprazole)
• selegiline
• selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, duloxetine, fluoxetine, paroxetine, sertraline)
• warfarin

Pregnancy & Lactation of Aspirin

FDA Pregnancy Category N – Not Assigned

Pregnancy 

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help healthcare providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

Lactation