Acetylsalicylic acid, better known as aspirin, is a nonsteroidal anti-inflammatory drug (NSAID) that is often used to treat mild pain, fever, and swelling. It has additional uses as a blood thinner and can effectively reduce the risk of a heart attack and stroke.
Generic names: Aspirin
Brand names: Ecotrin, Bayer, Aspergum, Aspirtab
Pharmacologic class: Nonsteroidal anti-inflammatory drug (NSAID)
Therapeutic class: Nonopioid analgesic, antipyretic, antiplatelet
Mechanism of action: Aspirin’s anti-inflammatory action works by inhibiting the activity of the enzyme cyclooxygenase (COX) which leads to the formation of prostaglandins that cause inflammation and subsequent pain and swelling.
Indications for use: Mild to moderate pain caused by inflammation such as rheumatoid arthritis. Fever reduction. Prevention of strokes, myocardial infarction (MI), and other thromboembolic disorders. Treats Kawasaki disease in children.
Precautions and contraindications: Do not use if sensitive to other NSAIDs or salicylates. Can cause renal or liver impairment. Excessive bleeding may occur if used with another anticoagulant. Do not use in the third trimester of pregnancy or when breastfeeding.
Drug Interactions
- Antacids may decrease the salicylate blood level
- ACE inhibitors may have a decreased antihypertensive effect
- Increased risk of bleeding when used with another anticoagulant, NSAID, or thrombolytic
- Corticosteroids may cause an increased salicylate excretion effect
- Furosemide may have an increased diuretic effect
- Increased risk of Reye’s syndrome if used with a live varicella vaccine
- May reduce the excretion of methotrexate leading to toxicity
- May reduce the effectiveness of spironolactone
- May reduce the absorption of tetracycline (buffered aspirin)
- Bleeding risk may increase when used with the following herbs: cayenne, chamomile, clove, garlic, ginger, ginkgo biloba, ginseng, and licorice
Adverse Effects
- Hearing loss, tinnitus, ototoxicity
- Nausea, vomiting, abdominal pain, heartburn
- GI bleeding or ulceration
- Thrombocytopenia, hemolytic anemia,
- Liver toxicity
- ↓ sodium, potassium, and glucose
- Wheezing, pulmonary edema with toxicity
- Rash, urticaria, bruising
Administration Considerations
Available preparations: chewable gum, tablets, chewable tablets, enteric-coated tablets, delayed and extended-release tablets, and suppositories.
Dosages for adults: Dosage is dependent on use. For pain, 2400 mg to 3600 mg in divided doses is initiated. 325 mg QID or 650 mg BID may be prescribed to prevent TIAs or stroke for those with a history. Aspirin 81 mg daily is often prescribed to prevent MI.
Dosages for children: Dose is dependent on weight. For pain or fever, 10 to 15 mg/kg PO or PR every 4 hours. For juvenile rheumatoid arthritis, 60 to 130 mg/kg/day is indicated for children weighing up to 55 lbs. 2400 mg to 3600 mg PO daily for children over 55 lbs, given in divided doses.
Route | Onset | Peak | Duration |
PO tablets | 15-30 minutes | 1-2 hours | 4-6 hours |
PO chewable | Rapid | Unknown | 1-4 hours |
PO enteric-coated | 5-30 minutes | 2-4 hours | 8-12 hours |
PO extended | 5-30 minutes | 1-4 hours | 3-6 hours |
Rectal | 5-30 minutes | 3-4 hours | 1-4 hours |
Nursing Considerations for Aspirin
Related Nursing Diagnoses
Nursing Assessment
- Assess for an allergy to NSAIDs or acetylsalicylic.
- Assess for pain by having the patient rate on a scale of 1-10, and describe characteristics, duration, and frequency.
- If given as an antipyretic, assess temperature.
- Assess for pregnancy or lactation. Aspirin is a category C/D risk meaning there is evidence of fetal harm but the benefit may outweigh the risk as determined by a healthcare professional.
- Assess for recent varicella vaccination. Aspirin should not be administered within 6 weeks of a live varicella vaccine due to the risk of Reye’s syndrome.
Nursing Interventions
- Routinely monitor the effectiveness of aspirin by assessing pain levels and fever reduction.
- Monitor for signs of toxicity: diplopia, EKG changes, seizures, hallucinations, hyperthermia, oliguria, acute renal failure, irritability, restlessness, tremor, confusion, lethargy, and anaphylaxis. The elderly are at a greater risk for toxicity.
- Closely monitor hemoglobin, hematocrit, INR, and renal function when prescribed long-term therapy.
- Activated charcoal can be administered for aspirin poisoning.
Patient Teaching Associated with Aspirin
- Instruct patients on symptoms of toxicity such as a ringing in the ears (tinnitus) or hearing loss, and unusual bleeding or bruising.
- Do not take aspirin with alcohol due to an increased risk of bleeding.
- Educate that aspirin has an antiplatelet effect. If the patient is taking another anticoagulant, their risk of bleeding is increased. Teach the patient to monitor for bruising and signs of bleeding, and to prevent the risk of injury.
- Keep out of reach of children to prevent poisoning.
- Aspirin needs to be discontinued 1 week prior to surgical and dental procedures due to the risk of bleeding. Discuss with your healthcare provider before discontinuing.
- Administer aspirin with food or milk to reduce the risk of GI irritation.
- Alert all providers that you are taking aspirin to prevent interactions.
- Do not break, crush, or chew extended-release, delayed-release, or enteric-coated preparations.
This is not an all-inclusive list of possible drug interactions, adverse effects, precautions, nursing considerations, or patient instructions. Please consult further with a pharmacist for complete information.
References and Sources
- Schull, P. D. (2013). McGraw-Hill Nurses Drug Handbook, Seventh Edition. McGraw-Hill Education.
- Vane JR, Botting RM. The mechanism of action of aspirin. Thromb Res. 2003 Jun 15;110(5-6):255-8. doi: 10.1016/s0049-3848(03)00379-7. PMID: 14592543.