aspirin (as-pir-in) acetylsalicylic acid, Acuprin, ASA, Asaphen, Aspergum, Aspir-Low, Aspirtab, Bayer Aspirin, Bayer Timed-Release Arthritic Pain Formula, Easprin, Ecotrin, 8-Hour Bayer Timed-Release, Empirin, Entrophen, Halfprin, Healthprin, Lowprin, Norwich Aspirin, Novasen, Rivasa, Sloprin, St. Joseph Adult Chewable Aspirin, Therapy Bayer, ZORprin

 Indications

Inflammatory disorders including: Rheumatoid arthritis,

Osteoarthritis. Mild to moderate pain. Fever. Prophylaxis

of transient ischemic attacks and MI. Unlabeled

Use: Adjunctive treatment of Kawasaki disease.

Action

Produce analgesia and reduce inflammation and fever

by inhibiting the production of prostaglandins. Decreases

platelet aggregation. Therapeutic Effects:

Analgesia. Reduction of inflammation. Reduction of fever.

Decreased incidence of transient ischemic attacks

and MI.

Pharmacokinetics

Absorption: Well absorbed from the upper small intestine;

absorption from enteric-coated preparations

may be unreliable; rectal absorption is slow and variable.

Distribution: Rapidly and widely distributed;

crosses the placenta and enters breast milk.

Metabolism and Excretion: Extensively metabolized

by the liver; inactive metabolites excreted by the

kidneys. Amount excreted unchanged by the kidneys

depends on urine pH; as pH increases, amount excreted

unchanged increases from 2–3% up to 80%.

Half-life: 2–3 hr for low doses; up to 15–30 hr with

larger doses because of saturation of liver metabolism.

TIME/ACTION PROFILE (analgesia/fever

reduction)

ROUTE ONSET PEAK DURATION

PO 5–30 min 1–3 hr 3–6 hr

Contraindications/Precautions

Contraindicated in: Hypersensitivity to aspirin or

other salicylates; Cross-sensitivity with other NSAIDs

may exist (less with nonaspirin salicylates); Bleeding

disorders or thrombocytopenia; Pedi: May increase risk

of Reye’s syndrome in children or adolescents with viral

infections.

Use Cautiously in: History of GI bleeding or ulcer

disease; Chronic alcohol use/abuse; Severe hepatic or

renal disease; OB: Salicylates may have adverse effects

on fetus and mother and should be avoided during

pregnancy, especially during the 3rd trimester; Lactation:

Safety not established; Geri:qrisk of adverse reactions

especially GI bleeding; more sensitive to toxic levels.

Adverse Reactions/Side Effects

EENT: tinnitus. GI: GI BLEEDING, dyspepsia, epigastric

distress, nausea, abdominal pain, anorexia, hepatotoxicity,

vomiting. Hemat: anemia, hemolysis. Derm:

rash, urticaria. Misc: allergic reactions including ANAPHYLAXIS

and LARYNGEAL EDEMA.

Interactions

Drug-Drug: Mayqthe risk of bleeding with warfarin,

heparin, heparin-like agents, thrombolytic

agents, dipyridamole, clopidogrel, tirofiban, or

eptifibatide, although these agents are frequently used

safely in combination and in sequence. Ibuprofen:

may negate the cardioprotective antiplatelet effects of

low-dose aspirin. Mayqrisk of bleeding with cefotetan

and valproic acid. Mayqactivity of penicillins,

phenytoin, methotrexate, valproic acid, oral hypoglycemic

agents, and sulfonamides. Urinary

acidificationqreabsorption and mayqserum salicylate

levels. Alkalinization of the urine or the ingestion

of large amounts of antacidsqexcretion andpserum

salicylate levels. May blunt the therapeutic

response to diuretics and ACE inhibitors.qrisk of

GI irritation with NSAIDs.

Drug-Natural Products:qanticoagulant effect

and bleeding risk with arnica, chamomile, clove, feverfew,

garlic, ginger, ginkgo, Panax ginseng, and

others.

Drug-Food: Foods capable of acidifying the

urine (see Appendix K) mayqserum salicylate levels.

Route/Dosage

Pain/Fever

PO, Rect (Adults): 325–1000 mg every 4–6 hr (not

to exceed 4 g/day). Extended-release tablets—650

mg every 8 hr or 800 mg every 12 hr.

PO, Rect (Children 2–11 yr): 10–15 mg/kg/dose

every 4–6 hr; maximum dose: 4 g/day.

Inflammation

PO (Adults): 2.4 g/day initially;qto maintenance dose

of 3.6–5.4 g/day in divided doses (up to 7.8 g/day for

acute rheumatic fever).

PO (Children): 60–100 mg/kg/day in divided doses

(up to 130 mg/kg/day for acute rheumatic fever).

Prevention of Transient Ischemic Attacks

PO (Adults): 50–325 mg once daily.

Prevention of Myocardial Infarction/Antiplatelet

Effects

PO (Adults): 80–325 mg once daily. Suspected acute

MI—160 mg as soon as MI is suspected.

PO (Children): 3–10 mg/kg/day given once daily

(round dose to a convenient amount).

Kawasaki Disease

PO (Children): 80–100 mg/kg/day in 4 divided

doses until fever resolves; may be followed by maintenance

dose of 3–5 mg/kg/day as a single dose for up

to 8 wk. 

Availability (generic available) A

Tablets: 81 mgOTC, 162.5 mgOTC, 325 mgOTC, 500

mgOTC, 650 mgOTC, 975 mgOTC. Chewable tablets:

80 mgOTC, 81 mgOTC. Chewing gum: 227 mgOTC.

Dispersible tablets: 325 mgOTC, 500 mgOTC. Entericcoated

(delayed-release) tablets: 80 mgOTC, 165

mgOTC, 300 mgOTC, 325 mgOTC, 500 mgOTC, 600

mgOTC, 650 mgOTC, 975 mgOTC. Extended-release tablets:

325 mgOTC, 650 mgOTC, 800 mg. Delayed-release

capsules: 325 mgOTC, 500 mgOTC. Suppositories:

60 mgOTC, 120 mgOTC, 125 mgOTC, 130 mgOTC,

150 mgOTC, 160 mgOTC, 195 mgOTC, 200 mgOTC,

300 mgOTC, 320 mgOTC, 325 mgOTC, 600 mgOTC,

640 mgOTC, 650 mgOTC, 1.2 gOTC. In combination

with: antihistamines, decongestants, cough

suppressantsOTC, opioids, and omeprazole (Yosprala).

See Appendix B.