Ibuprofen inhibits the activity of the enzyme cyclo - oxygenase, resulting in decreased formation of precursors of prostaglandins and thromboxanes from arachidonic acid.
Analgesic - Ibuprofen may block pain impulse generation via a peripheral action that may involve reduction of the prostaglandins, and possibly inhibition of the synthesis or actions of other substances that sensitize pain receptors to mechanical or chemical stimulation.
Antipyretic - Ibuprofen probably produces antipyresis by acting centraIly on the hypothalamic heat - regulating center to produce peripheral vasodilation, resulting in increased blood flow through the skin, sweating, and heat loss. The central action probably involves reduction of prostaglandin activity in the hypothalamus.

Indicated for rheumatoid arthritis, osteoarthritis, juvenile arthritis, and psoriatic arthritis; pain; gouty arthritis or calcium pyrophosphate deposition disease (pseudogout); fever; and dysmenorrhea. May also be used for prophylaxis and treatment of vascular headaches.

Risk - benefit should be considered when the foIlowing medical problems exist:
Allergic reaction, mild, such as aIlergic rhinitis, urticaria, or skin rash, induced by aspirin or other NSAIDs, history of (possibility of cross- sensitivity); anemia; asthma; hypertension; renal or hepatic function impairment or failure; edema; congestive heart disease; inflammatory or ulcerative disease of the upper or lower gastrointestinal tract, including crohn's disease, diverticulitis, peptic ulcer disease, or ulcerative colitis, active or history of; hemophilia or other bleeding problems; alcoholism; diabetes meIlitus; systemic lupus erythematosus; edema; stomatitis.

ln addition to the interactions listed below, the possibility should be considered that additive or multiple effects leading to impaired blood clotting and / or increased risk of bleeding may occur if any NSAID is used concurrently with any medication having a significant potential for causing hypoprothrombinemia , thrombocytopenia , or gastrointestinal ulceration or hemorrhage.
Cyclosporine - Gold compounds - Digoxin - Lithium - Probenecid - Acetaminophen - Anticoagulants - Potassium supplements - Antihypertensives - Diuretics such as triamterene - Salicylates - Alcohol - Corticosteroids - Valproic acid - Antidiabetic agents.

Hypersensitivity reactions such as: Rhinosinusitis / asthma or angioedema / urticaria; anaphylaxis.
In addition, a syndrome of fever and chills, nausea, vomiting, and abdominal pain has been reported with ibuprofen, and a serum sickness- or influenza-like syndrome that may consist of troubled breathing, arthralgias, fever and chills, fatigue, pruritus, and / or skin rash or other cutaneous manifestations, has been reported with ibuprofen.
Gastrointestinal problems; headache; renal and hepatic function impairment; CNS effects; edema; hyperkalemia; hearing problems.

Usual adult and adolescent dose :
Antirheumatic (nonsteroidal anti -inflammatory): Oral, 1200 to 3200 mg a day in 3 or 4 divided doses. After a satisfactory response has been obtained, dosage should be reduced to the lowest maintenance dose that provides continuing control of symptoms.
Note: Higher doses generally are required in rheumatoid arthritis than in osteoarthritis.
Analgesic (mild to moderate pain); antipyretic; antidysmenorrheal - Oral, 200 to 400 mg every 4 to 6 hours as needed.
Usual adult prescribing limits :
Antirheumatic (nonsteroidal anti - inflammatory) -Up to 3600 mg per day. The maximum dosage should be used only if the clinical benefit is increased sufficiently to offset the higher risk of adverse effects. Analgesic; antipyretic; antidysmenorrheal - for patient self - medication (over - the - counter use): Not to exceed 1200 mg per day. Usual pediatric dose:
Antirheumatic (nonsteroidal anti -inflammatory) - Children 6 months to 12 years of age: Oral, initially 30 to 40 mg per kg of body weight a day in 3 or 4 divided doses, although 20 mg per kg of body weight per day may be sufficient for patients with mild disease. After a satisfactory response has been achieved, dosage should be reduced to the lowest dose needed to control disease activity.
Antipyretic - Children 6 months to 12 years of age: Oral, 5 mg per kg of body weight for fevers lessthan 39.17°C (102.5°F) and 10 mg per kg of body weight for higher fevers. Dosage may be repeated, if necessary, at intervals of 4 to 6 hours or more.
Usual pediatric prescribing limits:
Antirheumatic - Oral, 50 mg per kg of body weight per day.
Antipyretic - Oral, 40 mg per kg of body weight per day.