Nonsteroidal anti-inflammatory drug prescribing: past, present, and future

A turbulent decade for NSAIDs: update on current concepts of classification, epidemiology, comparative efficacy, and toxicity

Non-steroidal anti-inflammatory drugs (NSAIDs) represent a diverse class of drugs and are among the most commonly used analgesics for arthritic pain worldwide, though long-term use is associated with a spectrum of adverse effects. The introduction of cyclooxygenase-2-selective NSAIDs early in the last decade offered an alternative to traditional NSAIDs with similar efficacy and improved gastrointestinal tolerability; however, emerging concerns about cardiovascular safety resulted in the withdrawal of two agents (rofecoxib and valdecoxib) in the mid-2000s and, subsequently, in an overall reduction in NSAID use. It is now understood that all NSAIDs are associated with some varying degree of gastrointestinal and cardiovascular risk. Guidelines still recommend their use, but little is known of how patients use these agents. While strategies and guidelines aimed at reducing NSAID-associated complications exist, there is a need for evidence-based algorithms combining cardiovascular and gastrointestinal factors that can be used to aid treatment decisions at an individual patient level.

The PPAR-Platelet Connection: Modulators of Inflammation and Potential Cardiovascular Effects

Historically, platelets were viewed as simple anucleate cells responsible for initiating thrombosis and maintaining hemostasis, but clearly they are also key mediators of inflammation and immune cell activation. An emerging body of evidence links platelet function and thrombosis to vascular inflammation. peroxisome proliferator-activated receptors (PPARs) play a major role in modulating inflammation and, interestingly, PPARs (PPARβ/δ and PPARγ) were recently identified in platelets. Additionally, PPAR agonists attenuate platelet activation; an important discovery for two reasons. First, activated platelets are formidable antagonists that initiate and prolong a cascade of events that contribute to cardiovascular disease (CVD) progression. Dampening platelet release of proinflammatory mediators, including CD40 ligand (CD40L, CD154), is essential to hinder this cascade. Second, understanding the biologic importance of platelet PPARs and the mechanism(s) by which PPARs regulate platelet activation will be imperative in designing therapeutic strategies lacking the deleterious or unwanted side effects of current treatment options.

The outpatient utilization of non-steroidal anti-inflammatory drugs in South Bačka District, Serbia

OBJECTIVE

To evaluate the utilization of non-steroidal anti-inflammatory drugs (NSAIDs) in South Bačka District (SBD), Serbia.

SETTING

State-owned and private pharmacies in SBD, a northern district of Serbia, with 605,720 inhabitants (according to the 2008 census).

METHOD

Data on the number of packages, size of packages, and retail price of NSAIDs (Anatomical Therapeutic Chemical (ATC) group M01A) from 1 January to 31 March 2008 were obtained from all state-owned and private pharmacies in SBD. This included NSAIDs bought without prescription and those issued by prescription (on the Health Insurance Companies List for Reimbursement). The number of defined daily doses/1000 inhabitants/day (DDD/1000 inh/day) was calculated. Within the DU90% (drug utilization 90%) segment, the proportion of high-, medium- and low-risk NSAIDs with respect to the risk of gastrointestinal (GI) bleeding was determined. Price/DDD was also calculated.

MAIN OUTCOME MEASURE

Consumption of drugs expressed as DDD/1000 inh/day.

RESULTS

The total consumption of NSAIDs over a 3-month period was 48.31 DDD/1000 inh/day. Only four drugs were within DU90%: diclofenac, ibuprofen, nimesulide and meloxicam (62.14, 19.87, 5.77, and 5.73% of total NSAID consumption, respectively). All dispensed NSAIDs within the DU90% segment except nimesulide (which was exclusively purchased without prescription) were nearly equally purchased without prescription and issued by prescription. The average price per DDD within the DU90% segment was 0.17 Euro/DDD, whereas it was 0.30 Euro/DDD for NSAIDs beyond the DU90% segment. The pattern of use of NSAIDs according to their GI risk showed that medium-risk diclofenac accounted for 66.45%, whereas low-risk ibuprofen was estimated to be 21.25% within the DU90% segment.

CONCLUSION

Factors other than evidence-based medicine (such as poor health education in the past that led to long-lasting consequences on the cultural behaviour of the general population as well as on the prescribing habits of physicians) have a dominating impact on the use of NSAIDs in SBD. Targeted education from independent sources in the prescribing, dispensing and use of drugs is required to improve the quality of prescription and use of NSAIDs in Serbia.

Risk management of risk management: Combining proton pump inhibitors with low-dose aspirin

Low-dose aspirin is widely used in the primary and secondary prevention of cardiovascular events, but is associated with a range of upper gastrointestinal side effects. In this review, we summarize the rationale for low-dose aspirin therapy, quantify the risk for upper gastrointestinal side effects, identify the risk factors involved, and provide an overview of preventive strategies, thereby focusing on the rationale and clinical utility of combining proton-pump inhibitors with low-dose aspirin.

Nonsteroidal antiinflammatory drug-related injury to the gastrointestinal tract: clinical picture, pathogenesis, and prevention

Increasing life expectancy in developed countries has led to a growing prevalence of arthritic disorders, which has been accompanied by increasing prescriptions for nonsteroidal antiinflammatory drugs (NSAIDs). These are the most widely used agents for musculoskeletal and arthritic conditions. Although NSAIDs are effective, their use is associated with a broad spectrum of adverse reactions in the liver, kidney, cardiovascular system, skin, and gut. Gastrointestinal (GI) side effects are the most common. The dilemma for the physician prescribing NSAIDs is, therefore, to maintain the antiinflammatory and analgesic benefits, while reducing or preventing GI side effects. The challenge is to develop safer NSAIDs by shifting from a focus on GI toxicity to the increasingly more appreciated cardiovascular toxicity.

Adverse effects of non-steroidal anti-inflammatory drugs (NSAIDs, aspirin and coxibs) on upper gastrointestinal tract

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most widely prescribed medication in the world. Their main benefit derives from their anti-inflammatory and analgesic effect, but the use of these agents is not innocuous since they mainly increase the risk of gastrointestinal (GI) and cardiovascular complications compared with non-NSAID users. NSAIDs injures the upper and lower gut by depleting COX-1 derived prostaglandins and causing topical injury to the mucosa. The risk of upper GI complications varies, depending on the presence of one or more risk factors. Among them, the three main risk factors are prior history of peptic ulcer, the single most important risk factor, age, the most common, and concomitant aspirin use, due to their GI and cardiovascular implications. Those individuals at-risk should be considered for alternatives to NSAID therapy and modifications of risk factors. If NSAID therapy is required, patients at risk will need prevention strategies including co-therapy of NSAID with gastroprotectants (PPI or misoprostol) or the prescription of COX-2 selective inhibitors. The probable introduction of NO-NSAIDs in the market in the near future may open a new therapeutic option for patients with hypertension who need NSAIDs.

Non-steroidal anti-inflammatory drug use in the elderly

The efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) for the treatment of inflammation and pain of various origins is well established. Prescribing these drugs, however, remains a challenge because a great variety of gastrointestinal and cardiovascular safety issues need to be considered, particularly in older patients. Recent recommendations suggest that the prescription of non-selective NSAIDs and/or selective cyclo-oxygenase-2 inhibitors (coxibs) may be appropriate in patients with low gastrointestinal risk (no prior gastrointestinal events, no concomitant treatments with other damaging drugs). Gastroprotection is appropriate in patients with gastrointestinal risk factors and in older patients. In patients at high risk for gastrointestinal and cardiovascular events, however, NSAID or coxib prescriptions are contraindicated. Multidimensional impairment is a crucial point in evaluating the clinical outcome of older patients; thus, a comprehensive geriatric assessment is useful in predicting adverse outcomes, including morbidity and mortality.

Drug-related damage of the ageing gastrointestinal tract

Drug use increases with age and the elderly is at increased risk of adverse drug reactions. Gastrointestinal adverse effects are one of the most often reported. Serious event are mostly caused by NSAIDs and/or aspirin which are the most widely prescribed medications in the world. NSAIDs and/or aspirin use are associated with complications from both the upper and the lower gastrointestinal tract. The risk of these complications depends on presence of risk factors, and age is the most frequent and relevant one. At-risk patients should be on prevention strategies including the use of the lowest effective dose, co-therapy with a gastroprotective agents or use of a COX-2 selective agent. Treatment of Helicobacter pylori infection is beneficial in patients starting therapy with these agents, especially in the presence of ulcer history. The best strategy to prevent lower GI complications has yet to be defined.

Comparison of nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 (COX-2) inhibitors use in Australia and Nova Scotia (Canada)

AIMS

Cyclooxygenase-2 (COX-2) inhibitors were marketed aggressively and their rapid uptake caused safety concerns and budgetary challenges in Canada and Australia. The objectives of this study were to compare and contrast COX-2 inhibitors and nonselective nonsteroidal anti-inflammatory drug (ns-NSAID) use in Nova Scotia (Canada) and Australia and to identify lessons learned from the two jurisdictions.

METHODS

Ns-NSAID and COX-2 inhibitor Australian prescription data (concession beneficiaries) were downloaded from the Medicare Australia website (2001-2006). Similar Pharmacare data were obtained for Nova Scotia (seniors and those receiving Community services). Defined daily doses per 1000 beneficiaries day(-1) were calculated. COX-2 inhibitors/all NSAIDs ratios were calculated for Australia and Nova Scotia. Ns-NSAIDs were divided into low, moderate and high risk for gastrointestinal side-effects and the proportions of use in each group were determined. Which drugs accounted for 90% of use was also calculated.

RESULTS

Overall NSAID use was different in Australia and Nova Scotia. However, ns-NSAID use was similar. COX-2 inhibitor dispensing was higher in Australia. The percentage of COX-2 inhibitor prescriptions over the total NSAID use was different in the two countries. High-risk NSAID use was much higher in Australia. Low-risk NSAID prescribing increased in Nova Scotia over time. The low-risk/high-risk ratio was constant throughout over the period in Australia and increased in Nova Scotia.

CONCLUSIONS

There are significant differences in Australia and Nova Scotia in use of NSAIDs, mainly due to COX-2 prescribing. Nova Scotia has a higher proportion of low-risk NSAID use. Interventions to provide physicians with information on relative benefits and risks of prescribing specific NSAIDs are needed, including determining their impact.

Systematic review: the global incidence and prevalence of peptic ulcer disease

BACKGROUND

Peptic ulcer disease (PUD) is most commonly associated with Helicobacter pylori infection and the use of acetylsalicylic acid (ASA) and nonsteroidal anti-inflammatory drugs (NSAIDs). The management of H. pylori infection has improved radically in recent years; however, the prescription of ASA and NSAIDs has increased over the same period.

AIM

To evaluate the current global incidence and prevalence of PUD by systematic review of the literature published over the last decade.

METHODS

Systematic searches of PubMed, EMBASE and the Cochrane library.

RESULTS

The annual incidence rates of PUD were 0.10-0.19% for physician-diagnosed PUD and 0.03-0.17% when based on hospitalization data. The 1-year prevalence based on physician diagnosis was 0.12-1.50% and that based on hospitalization data was 0.10-0.19%. The majority of studies reported a decrease in the incidence or prevalence of PUD over time.

CONCLUSIONS

Peptic ulcer disease remains a common condition, although reported incidence and prevalence are decreasing. This decrease may be due to a decrease in H. pylori-associated PUD.

Interactions of ibuprofen with hybrid lipid bilayers probed by complementary surface-enhanced vibrational spectroscopies

The incorporation of small molecules into lipid bilayers is a process of biological importance and clinical relevance that can change the material properties of cell membranes and cause deleterious side effects for certain drugs. Here we report the direct observation, using surface-enhanced Raman and IR spectroscopies (SERS, SEIRA), of the insertion of ibuprofen molecules into hybrid lipid bilayers. The alkanethiol-phospholipid hybrid bilayers were formed onto gold nanoshells by self-assembly, where the underlying nanoshell substrates provided the necessary enhancements for SERS and SEIRA. The spectroscopic data reveal specific interactions between ibuprofen and phospholipid moieties and indicate that the overall hydrophobicity of ibuprofen plays an important role in its intercalation in these membrane mimics.

Nonsteroidal anti-inflammatory drugs: adverse effects and their prevention

OBJECTIVES

To discuss nonsteroidal anti-inflammatory drugs (NSAIDs), their history, development, mode of action, toxicities, strategies for the prevention of toxicity, and future developments.

METHODS

Medline search for articles published up to 2007, using the keywords acetylsalicylic acid, aspirin, NSAIDs, cyclooxygenase 2, adverse effects, ulcer, and cardiovascular.

RESULTS

NSAIDs are 1 of the oldest, most successful drugs known to modern medicine. They are effective for alleviating pain, fever, and inflammation by inhibiting prostaglandin synthesis. Aspirin, by its irreversible inhibition of blood platelet function, is also effective in the prevention of cardiovascular disease. NSAIDs may cause gastrointestinal ulcers, serious cardiovascular events, hypertension, acute renal failure, and worsening of preexisting heart failure. These adverse effects may be prevented by limiting NSAID dosage and duration and by performing individual risk assessments and treating patients accordingly. Those at risk for gastroduodenal ulcers may be treated with concomitant proton-pump inhibitors, misoprostol and/or COX-2 selective NSAIDs. Those at risk for cardiovascular events may be treated with naproxen and a proton-pump inhibitor or misoprostol, but should best avoid NSAID use altogether.

CONCLUSIONS

Physicians should always prescribe the lowest effective dose for the shortest possible time and must take into account both the gastrointestinal and the cardiovascular risks of individual patients when prescribing NSAIDs.

Non-steroidal anti-inflammatory drugs, Cyclooxygenase-2 inhibitors and paracetamol use in Queensland and in the whole of Australia

BACKGROUND

Cross national drug utilization studies can provide information about different influences on physician prescribing. This is important for medicines with issues around safety and quality of use, like non selective non-steroidal anti-inflammatory drugs (ns-NSAIDs) and cyclo-oxygenase-2 (COX-2) inhibitors. To enable comparison of prescription medicine use across different jurisdictions with a range of population sizes, data first need to be compared within Australia to understand whether use in a smaller sub-population may be considered as representative of the total use within Australia. The aim of this study was to compare the utilization of non selective NSAID, COX-2 inhibitors and paracetamol between Queensland and Australia.

METHOD

Dispensing data were obtained for concession beneficiaries for Australia for ns-NSAIDs, COX-2 inhibitors and paracetamol subsidized by the PBS over the period 1997-2003. The same data were purchased for Queensland. Data were converted to Defined Daily Dose (DDD)/1000 beneficiaries/day (World Health Organization anatomical therapeutic chemical classification, 2005).

RESULTS

Total NSAID and paracetamol consumption were similar in Australia and Queensland. Ns-NSAID use decreased sharply with the introduction of COX-2 inhibitors (from approximately 80 to 40 DDD/1000 beneficiaries/day). Paracetamol was constant (approximately 45 DDD/1000 beneficiaries/day). COX-2 inhibitors consumption was initially higher in Queensland than in the whole of Australia.

CONCLUSION

Despite initial divergence in celecoxib use between Queensland and Australia, the use of ns-NSAIDs, COX-2 inhibitors and paracetamol overall, in concession beneficiaries, was comparable in Australia and Queensland.

Fatores associados ao uso de antiinflamatórios não esteróides em população de funcionários de uma universidade no Rio de Janeiro: Estudo Pró-Saúde

Os Antiinflamatórios Não-Esteróides (AINE) estão entre os medicamentos mais utilizados no mundo. Estima-se que mais de 30 milhões de pessoas tomem AINE diariamente, apesar de sua toxicidade e de seus efeitos adversos, principalmente gastrointestinais. O presente trabalho utilizou dados seccionais da Fase 1 (1999) de um estudo de coorte (Estudo Pró-Saúde) coletados entre 4.030 funcionários técnico-administrativos de uma universidade no Rio de Janeiro, nos quais foram aplicados questionários autopreenchíveis. Nesse estudo, os AINE apareceram entre os principais produtos consumidos nas duas semanas que antecederam à pesquisa, com prevalência de 7%. Verificou-se que as mulheres têm maior chance de serem usuárias (OR = 2,11; IC 95%: 1,59 - 2,79). Os dados foram submetidos a análise multivariada, tendo sido propostos modelos logísticos por sexo. A carga horária trabalhada na semana foi um importante preditor do uso de AINE (OR = 1,03; IC 95%: 1,01 - 1,04, para homens, e OR = 1,02; IC 95%: 1,00 - 1,03, para mulheres). Dor incapacitante e artrose também se mostraram relevantes, com OR = 2,89 (IC 95%: 1,77 - 4,71) e OR = 2,29 (IC 95%: 1,10 - 4,75), respectivamente, para os homens, e OR = 2,65 (IC 95%: 1,89 - 3,70) e OR = 2,00 (IC 95%: 1,37 - 2,93), respectivamente, para as mulheres. Outros preditores importantes foram a hérnia de disco (OR = 2,27; IC 95%: 0,93 - 5,54) para os homens, e LER (OR = 1,64; IC 95%: 1,15 - 2,35), cálculos vesical (OR = 1,85; IC 95%: 1,00 - 3,45) e renal (OR = 1,81; IC 95%: 1,12 - 2,91) para as mulheres. Mulheres e indivíduos com maior carga horária de trabalho semanal constituem grupos mais vulneráveis, em termos de uso irracional, e, portanto, mais sujeitos a programas de intervenção. Os resultados apontam para a importância das condições de trabalho no processo de desencadeamento de doenças.

Is ranitidine therapy sufficient for healing peptic ulcers associated with non-steroidal anti-inflammatory drug use?

Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) increases the risk of serious gastroduodenal events. To minimise these risks, patients often require concomitant acid-suppressive therapy. We conducted a literature review of clinical trials examining use of ranitidine 150 mg twice daily to heal gastroduodenal ulcers (GU) in NSAID recipients. Seven studies were identified. After 8 weeks' treatment with ranitidine, GU healing rates ranged from 50% to 74% and rates of duodenal ulcer (DU) healing ranged from 81% to 84%. Ranitidine was more effective when NSAIDs were discontinued (healing rates reaching 95% and 100%, respectively). The ulcer healing rate with sucralfate was similar to that of ranitidine. However, proton pump inhibitor (PPI) therapy was associated with significantly greater rates of both GU and DU healing than ranitidine; 8-week GU rates were 92% and 88% with esomeprazole 40 mg and 20 mg, respectively (vs. 74% with ranitidine, p < 0.01). For omeprazole, 8-week healing rates were 87% with omeprazole 40 mg and 84% with omeprazole 20 mg (vs. 64% for ranitidine, p < 0.001), and for lansoprazole the corresponding values were 73-74% and 66-69% for the 30 mg and 15 mg doses, respectively (vs. 50-53% for ranitidine, p < 0.05). In the PPI study reporting DU healing the values were 92% for omeprazole 20 mg (vs. 81% for ranitidine, p < 0.05) and 88% for omeprazole 40 mg (p = 0.17 vs. ranitidine). NSAID-associated GU are more likely to heal when patients receive concomitant treatment with a PPI rather than ranitidine.

The historical analysis of aspirin discovery, its relation to the willow tree and antiproliferative and anticancer potential

For several millennia, the willow tree and salicin have been associated with salicylic acid, the key precursor molecule that has contributed to the discovery of acetylsalicylic acid, traded as aspirin. These molecules have been shown to possess phyto- and chemotherapeutic activities as analgesic drugs. In recent decades, aspirin has become the focus of extensive investigation into antiproliferative and anticancer activities. The historical steps that led to the discovery of aspirin, and its antiproliferative and anticancer potential are highlighted in this review.

NSAID-associated adverse effects and acid control aids to prevent them: a review of current treatment options

NSAIDs are central to the clinical management of a wide range of conditions. However, NSAIDs in combination with gastric acid, which has been shown to play a central role in upper gastrointestinal (GI) events, can damage the gastroduodenal mucosa and result in dyspeptic symptoms and peptic lesions such as ulceration.NSAID-associated GI mucosal injury is an important clinical problem. Gastroduodenal ulcers or ulcer complications occur in up to 25% of patients receiving NSAIDs. However, these toxicities are often not preceded by indicative symptoms. Data obtained from the Arthritis, Rheumatism, and Aging Medical Information System have shown that 50-60% of NSAID-associated peptic ulcer cases can remain clinically silent and do not present until complications occur. Therefore, prophylactic treatment to prevent GI complications may be necessary in a substantial proportion of NSAID users, especially those in groups associated with a high risk of developing these complications. Use of cyclo-oxygenase (COX)-2 selective NSAIDs, also known as 'coxibs', substantially reduces the incidence of upper GI toxicities seen with non-selective NSAIDs. However, there are concerns regarding the cardiovascular safety of coxibs. For this reason, the US FDA recommends minimal use of coxibs and only when strictly necessary. Additionally, rofecoxib has been removed from the US market and sales of valdecoxib have been suspended. Furthermore, upper GI toxicities still occur in patients receiving coxibs. Therefore, cotherapies are required to prevent and/or heal upper GI effects associated with NSAID use. Effective prophylactic and treatment strategies include misoprostol, histamine H(2) receptor antagonists and proton pump inhibitors (PPIs). The key role that gastric acid plays in upper GI adverse events among NSAID users suggests that it is important to choose the most effective agent for acid control to alleviate symptoms, heal mucosal erosions and improve the reduced quality of life in this patient population. PPIs provide effective acid suppression, which is essential to avoid GI mucosal injury, and they are, therefore, capable of dramatically decreasing the morbidity and mortality associated with this disorder. Since many serious GI complications are not heralded by any previous symptoms, physicians need to be aware of risk factor profiles that predispose patients to serious GI problems. Physicians also need to initiate the appropriate preventative acid suppressive therapy to minimise the burden of NSAID-associated GI adverse effects.

Prevention of anti-inflammatory drug-induced gastrointestinal damage: benefits and risks of therapeutic strategies

Patients who take non-steroidal anti-inflammatory drugs (NSAIDs) may develop serious gastrointestinal (GI) side effects in both the upper and lower GI tract. Those at risk should be considered for prevention with misoprostol, proton pump inhibitor (PPI) or COX-2 selective inhibitor (coxib) therapy. A coxib or an NSAID+PPI combination is considered to have comparable GI safety profiles, but evidence from direct comparison is limited. PPIs are effective in the prevention of upper GI events in endoscopy trials and in a few, small, outcome trials in patients at risk. Coxibs have been evaluated in endoscopic ulcer studies and clinical outcome trials, and shown to significantly reduce the risk of upper GI ulcer and complications. Moreover, unlike PPIs, coxibs significantly reduce toxicity in the lower GI tract compared with NSAIDs. Coxibs and possibly some NSAIDs also increase the risk of developing serious cardiovascular events, an effect which may depend on the drug, dose and duration of therapy. It is not known whether concomitant low-dose aspirin use, which occurs in more than 20% of patients, will reduce the incidence of cardiovascular events, although concomitant aspirin increases the risk of developing serious GI events in patients taking either an NSAID or a coxib. Such patients may require additional PPI co-therapy. Current prevention strategies with an NSAID+PPI, misoprostol or a coxib must be considered in the individual patient with GI and cardiovascular risk factors. A PPI+coxib is indicated in those at highest risk (e.g. previous ulcer bleeding). PPI therapy must be considered for the treatment and prevention of NSAID-induced dyspepsia.

NSAID-related psychiatric adverse events: who is at risk?

NSAIDs are frequently used in clinical practice and they account for approximately 5-10% of all drug prescriptions. NSAID use has been associated with a risk of adverse events, which have a relevant impact on morbidity and mortality and account for a substantial increment of healthcare costs. Less common, but clinically relevant, adverse events associated with NSAID use are the impairment of the CNS and, particularly, the appearance of psychiatric symptoms. These symptoms include changes in cognition, mood state and even precipitation or exacerbation of pre-existing psychiatric disorders. This article aims to review the medical literature on published reports of NSAID-related psychiatric adverse events, identify risk factors for these events and describe mechanisms potentially involved in their onset. We identified 27 reports with data on 453 cases of NSAID-related psychiatric adverse events. Data suggest that individuals who may be particularly susceptible to such events include patients with a history of psychiatric illness and possibly parturients. Indometacin and selective cyclo-oxygenase (COX)-2 inhibitors were the most frequently reported culprit drugs; however, whether this reflects an increased incidence with these drugs compared with other NSAIDs or factors such as usage or reporting patterns is unknown.A possible explanation for the psychiatric effect of NSAIDs resides in the modulation of central neurotransmission by prostaglandins, the synthesis of which is inhibited by NSAIDs. COX-2 is a key enzyme in this process since its activity is localised in distal dendrites and dendritic spines, which are cellular specialisations involved in synaptic signalling. Dopamine is considered the most relevant neurotransmitter involved in this phenomenon. Psychiatric symptoms are a rare but relevant complication of NSAID use. This effect is probably a consequence of impairment in neurotransmission modulated by prostaglandins when NSAIDs are used by susceptible individuals. These drugs should be used with caution in high-risk individuals with pre-existing psychiatric illness, and caution may also be advisable in the postpartum period. To date, reports of NSAID-related psychiatric adverse events have most commonly involved indometacin and selective COX-2 inhibitors. Prescribers should consider warning patients of the possibility of an acute neuropsychiatric event when traditional NSAIDs or selective COX-2 inhibitors are prescribed.

Dose-ranging analgesic study of Prosorb diclofenac potassium in postsurgical dental pain

BACKGROUND

ProSorb diclofenac potassium (K) is a novel, liquid-filled rapid-dispersion formulation of the nonsteroidal anti-inflammatory drug diclofenac, placed into soft gelatin capsules. Its time to maximal plasma drug concentration has been shown to be approximately half, and its maximal plasma drug concentration nearly twice, that of immediate-release diclofenac K tablets.

OBJECTIVE

This study compared the analgesic dose-response relationship and tolerability of 3 doses of ProSorb diclofenac K and placebo in the treatment of pain after dental impaction surgery.

METHODS

This randomized, double-blind, double-dummy, placebo-controlled parallel-group study was conducted at 6 centers across the United States. Patients aged 18 to 65 years with moderate or severe pain after the removal of > or =1 impacted mandibular third molar were randomly assigned to receive a single dose of ProSorb diclofenac K 25, 50, or 100 mg or placebo. Pain intensity and relief were assessed up to 6 hours after dosing. Rescue treatment was allowed after 1 hour. Efficacy end points included the summed pain intensity difference over 3 and 6 hours (SPID3 and 6); total pain relief at 3 and 6 hours (TOTPAR3 and 6); median times to onset of perceptible and meaningful relief (analgesic onset) and rescue medication use (analgesic duration); and cumulative percentage of patients using rescue medication. Tolerability was assessed using vital sign measurements and spontaneous reporting of adverse events.

RESULTS

A total of 265 patients (154 women, 111 men; mean age, 23.3 years) were enrolled. All 3 ProSorb diclofenac K groups showed higher SPID6 and TOTPAR6 scores and longer median times to rescue medication use than the placebo group (all, P < 0.001). For these end points, a dose-response relationship was evident between the 100-mg dose and the 25- and 50-mg doses (P < or = 0.05); the 25- and 50-mg doses were similar. In the diclofenac groups, median onset times for first perceptible (< or =22.5 min) and meaningful (< or =53.0 min) relief were significantly more rapid than placebo (P < or = 0.01). Proportions of patients requiring rescue analgesic were < or =50.8% with diclofenac compared with 79.4% with placebo. Proportions of patients assigning a global evaluation of good or better was > or =68% with diclofenac compared with 21% for placebo. Tolerability was similar across all treatment groups.

CONCLUSION

In this study of patients treated for pain following dental impaction surgery, single doses of ProSorb diclofenac K 25, 50, and 100 mg were more efficacious than placebo with respect to reduction of pain. All 3 doses provided a rapid analgesic onset and were well tolerated.

Aspirin and NSAID sensitivity

Aspirin and the older nonsteroidal anti-inflammatory drugs (NSAIDs) that block cyclo-oxygenase-1 (COX-1) induce asthma attacks in patients with aspirin-exacerbated respiratory disease and urticaria in patients with chronic idiopathic urticaria. Weak inhibitors of COX-1, such as acetaminophen and salsalate, crossreact also but only with high doses of the drugs. Partial inhibitors of both COX-1 and COX-2, such as nimesulide and meloxicam, also cross-react but only at high drug doses. COX-2 inhibitors do not cross-react; however, all NSAIDs, including the selective COX-2 inhibitors, can sensitize patients and induce urticaria or anaphylaxis on next exposure to the drug.

Anaphylactic and anaphylactoid reactions to aspirin and other NSAIDs

Aspirin and non-steroidal antiinflammatory drugs (NSAIDs) may cause anaphylactic or anaphylactoid reactions. Constitutively-expressed cyclooxygenase (COX-1) inhibition is likely to be responsible for the cross-reactions and side effects associated with these drugs, as well as the anaphylactoid reactions sometimes seen in aspirin-sensitive respiratory disease. Though anaphylactic and anaphylactoid reactions may be clinically indistinguishable, they involve different mechanisms. Anaphylactic reactions are due to immediate hypersensitivity involving cross-linking of drug-specific IgE. Regardless of COX selectivity pattern, NSAIDs may function as haptens capable of inducing allergic sensitization. Unlike anaphylaxis, anaphylactoid reactions are most likely related to inhibition of COX-l by NSAIDS. Thus, an anaphylactoid reaction caused by a particular COX-1 inhibiting NSAID will occur with a chemically unrelated NSAID which also inhibits COX-1 enzymes. Selective COX-2 inhibitors appear to be safe in patients with a history of NSAID-related anaphylactoid reactions but can function as haptens, with resulting sensitization and anaphylaxis upon next exposure. This article will discuss the mechanisms, prevalence and population-based studies of anaphylactic and anaphylactoid reactions caused by aspirin and NSAIDs. The evaluation and management of patients suspected of having experienced an anaphylactic or anaphylactoid reaction to aspirin or other NSAIDs will also be reviewed.

Assessing the economic impact of adverse drug effects

Although most commonly used drugs cause adverse effects, some of them with potentially serious consequences, relatively little is known about their economic impact. The purpose of this review is to summarise information describing the cost of treatment of drug-induced adverse effects as an additional cost of pharmaceutical treatment. The focus of this study was limited to the overall economic impact of drug-related morbidity and to the economic analysis of a single class of drugs with different safety profiles. Several studies carried out in the US have investigated adverse drug effects experienced by hospitalised patients and their impact on hospital costs. Patients who developed adverse effects were hospitalised an average of 1.2-3.8 days longer than patients who did not, with additional hospital costs of $US2284-5640 per patient (2000 values). Other research studies in different countries have quantified the incidence and economic consequences of adverse drug effects that occur in the ambulatory setting and that generate hospital admission and emergency department visits. They have shown that preventable adverse effects constitute between 43.3% and 80% of all adverse outcomes leading to emergency visits and hospital admissions, and disproportionately increase healthcare costs. Finally, a recent estimation revealed that in the US the cost of problems linked to drug use in the ambulatory setting exceeded $US177 billion in the year 2000.NSAIDs constitute a widely used class of drugs and they are one of the leading drug classes in causing adverse effects. The acquisition costs of the drugs, as well as the costs for prevention and treatment of adverse effects, determine their cost-effectiveness ratio. Depending on the incidence and severity of adverse effects, the cost per adverse effect avoided ranges from $US215 to $US35 459 (2000 values). According to the contingent valuation methodology, willingness to pay to avoid or reduce the incidence of adverse effects is an indicator of the value individuals associate with the impact of such effects on their well-being. Individuals are willing to pay annually an average of $US240 and $US350, respectively, to avoid vomiting and gastrointestinal distress induced by NSAIDs. Although the results of the different studies reviewed are not strictly comparable because of differences in the severity of adverse effects, the perspective of the analysis, the cost data included and the cost component considered, the data show that, apart from the implications for health, a substantial quantity of resources are used to treat adverse effects.

Comparison of the analgesic efficacy of rofecoxib and enteric-coated diclofenac sodium in the treatment of postoperative dental pain: a randomized, placebo-controlled clinical trial

BACKGROUND

Rofecoxib is a selective cyclooxygenase-2 inhibitor indicated for the treatment of acute pain, with similar analgesic efficacy to ibuprofen and naproxen sodium. Diclofenac sodium is the most commonly prescribed nonsteroidal anti-inflammatory drug worldwide; it is effective for the treatment of pain as well as the signs and symptoms associated with the painful conditions of osteoarthritis and rheumatoid arthritis.

OBJECTIVE

The aim of this study was to compare the analgesic efficacy and tolerability of a single dose of rofecoxib 50 mg, 3 doses of enteric-coated diclofenac sodium 50 mg, and placebo over 8-hour and 24-hour periods in patients with moderate to severe pain after oral surgery.

METHODS

In this double-blind, placebo- and active comparator-controlled, parallel-group study, patients experiencing moderate to severe pain after the surgical extraction of > or = 2 third molars were randomized to receive a single dose of rofecoxib 50 mg, 3 doses of enteric-coated diclofenac sodium 50 mg (50 mg given every 8 hours), or placebo. Patients rated pain intensity, pain relief, and global assessments at prespecified times throughout the 24-hour period after initial dosing. Overall analgesic efficacy was determined by total pain relief over 8 hours (TOPAR8) and 24 hours (TOPAR24) and patient global assessments at 8 and 24 hours. Onset of analgesic effect was determined by using the 2-stopwatch method for confirmed perceptible pain relief. Peak analgesic effect was the maximum pain relief attained during the first 8 hours. The duration of analgesic effect was determined by median time to rescue analgesia use.

RESULTS

A total of 305 patients were randomized to treatment: 121 received rofecoxib, 121 received diclofenac sodium, and 63 received placebo. The baseline demographics were similar among the groups. Overall, 61.3% experienced moderate pain and 38.7% experienced severe pain; 53.1% were female; and the mean age was 23.4 years. The overall analgesic efficacy, as assessed by TOPAR8, of a single dose of rofecoxib 50 mg was significantly greater than a single dose of enteric-coated diclofenac sodium 50 mg (20.5 vs 8.2) and placebo (20.5 vs 5.9). Patient global assessment at 8 hours was also significantly better for rofecoxib compared with enteric-coated diclofenac sodium and placebo. TOPAR24 was significantly greater for a single dose of rofecoxib 50 mg compared with 3 doses of enteric-coated diclofenac sodium 50 mg (64.1 vs 25.1) and placebo (64.1 vs 19.2). At 24 hours, the patient global assessment for rofecoxib was significantly better than that achieved with enteric-coated diclofenac sodium and placebo. The onset of analgesic effect was significantly more rapid for rofecoxib than for enteric-coated diclofenac sodium and placebo (median times: 31 minutes, >4 hours, and >4 hours, respectively). The peak analgesic effect was significantly greater for rofecoxib compared with enteric-coated diclofenac sodium (3.2 vs 1.5) and placebo (3.2 vs 1.1). The duration of analgesia was significantly longer for rofecoxib than enteric-coated diclofenac sodium (median times: >24 hours vs 1 hour and 37 minutes) and placebo (>24 hours vs 1 hour and 37 minutes). Enteric-coated diclofenac sodium was numerically greater than placebo for the key end points measuring overall efficacy (total pain relief and patient global assessment), but diclofenac sodium did not provide as much analgesic effect as expected for a drug effective for pain, osteoarthritis, and rheumatoid arthritis and did not differ significantly from placebo. Overall, both rofecoxib and enteric-coated diclofenac sodium were generally well tolerated, although the rofecoxib group had a significantly lower incidence of clinical and drug-related adverse events than the enteric-coated diclofenac sodium group.

CONCLUSIONS

A single 50-mg dose of rofecoxib provided greater overall analgesic efficacy over 8 hours, more rapid onset of analgesia, greater maximum analgesic effect, and longer duration of effect than a single 50-mg dose of enteric-coated diclofenac sodium in patients with moderate to severe pain associated with oral surgery. Compared with 3 doses of enteric-coated diclofenac sodium 50 mg (50 mg every 8 hours), a single dose of rofecoxib 50 mg provided greater overall analgesic efficacy over 24 hours.