50th anniversary of the discovery of ibuprofen: an interview with Dr Stewart Adams

Objective To analyse the available evidence on cardiovascular safety of non-steroidal anti-inflammatory drugs. Design Network meta-analysis. Data sources Bibliographic databases, conference proceedings, study registers, the Food and Drug Administration website, reference lists of relevant articles, and reports citing relevant articles through the Science Citation Index (last update July 2009). Manufacturers of celecoxib and lumiracoxib provided additional data. Study selection All large scale randomised controlled trials comparing any non-steroidal anti-inflammatory drug with other non-steroidal anti-inflammatory drugs or placebo. Two investigators independently assessed eligibility. Data extraction The primary outcome was myocardial infarction. Secondary outcomes included stroke, death from cardiovascular disease, and death from any cause. Two investigators independently extracted data. Data synthesis 31 trials in 116 429 patients with more than 115 000 patient years of follow-up were included. Patients were allocated to naproxen, ibuprofen, diclofenac, celecoxib, etoricoxib, rofecoxib, lumiracoxib, or placebo. Compared with placebo, rofecoxib was associated with the highest risk of myocardial infarction (rate ratio 2.12, 95% credibility interval 1.26 to 3.56), followed by lumiracoxib (2.00, 0.71 to 6.21). Ibuprofen was associated with the highest risk of stroke (3.36, 1.00 to 11.6), followed by diclofenac (2.86, 1.09 to 8.36). Etoricoxib (4.07, 1.23 to 15.7) and diclofenac (3.98, 1.48 to 12.7) were associated with the highest risk of cardiovascular death. Conclusions Although uncertainty remains, little evidence exists to suggest that any of the investigated drugs are safe in cardiovascular terms. Naproxen seemed least harmful. Cardiovascular risk needs to be taken into account when prescribing any non-steroidal anti-inflammatory drug.

This review attempts to bring together information from a large number of recent studies on the clinical uses, safety and pharmacological properties of ibuprofen. Ibuprofen is widely used in many countries for the relief of symptoms of pain, inflammation and fever. The evidence for modes of action of ibuprofen are considered in relation to its actions in controlling inflammation, pain and fever, as well as the adverse effects of the drug. At low doses (800-1,200 mg day(-1)) which in many countries are approved for non-prescription (over-the-counter) sale ibuprofen has a good safety profile comparable with paracetamol. Its analgesic activity is linked to its anti-inflammatory effects and is related to reduction in the ex vivo production in blood of cyclo-oxygenase (COX)-1 and COX-2 derived prostanoids. Higher prescription doses (circa 1,800-2,400 mg day(-1)) are employed long-term for the treatment of rheumatic and other more severe musculo-skeletal conditions. Recent evidence from large-scale clinical trials with the newer coxibs, where ibuprofen was as a comparator, have confirmed earlier studies which have shown that ibuprofen has comparable therapeutic benefits with coxibs and other NSAIDs. For long-term usage (6+ months) there are greater numbers of drop-outs due to reduced effectiveness of therapy, a feature which is common with NSAIDs. Spontaneous reports of adverse events and adverse drug reactions (ADRs) in clinical trails from long-term coxib comparator studies, as well as in epidemiological studies, shows that ibuprofen has relatively low risks for gastro-intestinal (GI), hepato-renal and other, rarer, ADRs compared with other NSAIDs and coxibs. A slightly higher risk of cardiovascular (CV) events has been reported in some, but not all studies, but the risks are in general lower than with some coxibs and diclofenac. The possibility that ibuprofen may interfere with the anti-platelet effects of aspirin, though arguably of low grade or significance, has given rise to caution on its use in patients that are at risk for CV conditions that take aspirin for preventing these conditions. Paediatric use of ibuprofen is reviewed and the main results are that the drug is relatively safe and effective as a treatment of acute pain and fever. It is probably more effective than paracetamol as an antipyretic. This assessment of the safety and benefits of ibuprofen can be summarized thus: (1) Ibuprofen at OTC doses has low possibilities of serious GI events, and little prospect of developing renal and associated CV events. Ibuprofen OTC does not represent a risk for developing liver injury especially the irreversible liver damage observed with paracetamol and the occasional liver reactions from aspirin. (2) The pharmacokinetic properties of ibuprofen, especially the short plasma half-life of elimination, lack of development of pathologically related metabolites (e.g. covalent modification of liver proteins by the quinine-imine metabolite of paracetamol or irreversible acetylation of biomolecules by aspirin) are support for the view that these pharmacokinetic and notably metabolic effects of ibuprofen favour its low toxic potential. (3) The multiple actions of ibuprofen in controlling inflammation combine with moderate inhibition of COX-1 and COX-2 and low residence time of the drug in the body may account for the low GI, CV and renal risks from ibuprofen, especially at OTC doses.

We investigated whether nonsteroidal antiinflammatory drug use was associated with a lower risk for Parkinson's disease (PD) in a large cohort of US men and women. PD risk was lower among ibuprofen users than nonusers. Compared with nonusers, the relative risks were 0.73 for users of fewer than 2 tablets/week, 0.72 for 2 to 6.9 tablets/week, and 0.62 for 1 or more tablets/day (p trend = 0.03). No association was found between the use of aspirin, other nonsteroidal antiinflammatory drugs, or acetaminophen and PD risk. The results suggest that ibuprofen use may delay or prevent the onset of PD.