This review discusses the pharmacology, analgesic efficacy, safety and tolerability of topical NSAIDs, salicylates and capsaicin for the management of osteoarthritis (OA) pain. Topical therapies present a valuable therapeutic option for OA pain management, with substantial evidence supporting the efficacy and safety of topical NSAIDs, but less robust support for capsaicin and salicylates. We define topical therapies as those intended to act locally, in contrast to transdermal therapies intended to act systemically. Oral therapies for patients with mild to moderate OA pain include paracetamol (acetaminophen) and NSAIDs. Paracetamol has only weak efficacy at therapeutic doses and is hepatotoxic at doses >3.25 g/day. NSAIDs have demonstrated efficacy in patients with OA, but are associated with dose-, duration- and age-dependent risks of gastrointestinal, cardiovascular, renal, haematological and hepatic adverse events (AEs), as well as clinically meaningful drug interactions. To minimize AE risks, treatment guidelines for OA suggest minimizing NSAID exposure by prescribing the lowest effective dose for the shortest duration of time. Systemic NSAID exposure may also be limited by prescribing topical NSAIDs, particularly in patients with OA pain limited to a few superficial joints. Topical NSAIDs have been available in Europe for decades and were introduced to provide localized analgesia with minimal systemic NSAID exposure. Guidelines of the American Academy of Orthopaedic Surgeons, European League Against Rheumatism (EULAR), Osteoarthritis Research Society International, and National Institute for Health and Clinical Excellence (NICE) state that topical NSAIDs may be considered for patients with mild to moderate OA of the knee or hand, particularly in patients with few affected joints and/or a history of sensitivity to oral NSAIDs. In fact, the EULAR and NICE guidelines state that topical NSAIDs should be considered before oral therapies. Clinical trials of topical NSAIDs, most notably formulations of diclofenac and ketoprofen, have shown efficacy significantly superior to placebo and similar to oral NSAIDs. Most topical NSAIDs (piroxicam being the exception) have shown improved safety and tolerability compared with oral NSAIDs. Topical salicylates and capsaicin are available in the US without a prescription, but neither has shown substantial efficacy in clinical trials, and both have potential to cause serious AEs. Accidental poisonings have been reported with salicylates, and concerns exist that capsaicin-induced nerve desensitization is not fully reversible and that its autonomic nerve effects may increase the risk of skin ulcers in diabetic patients.
DSG was effective and generally well tolerated in adults regardless of age. These data support the topical application of DSG for relief of OA knee pain in elderly and younger patients. Clinicaltrials.gov registration numbers NCT00171626, NCT00171678, NCT00426621.
IntroductionNonsteroidal anti-inflammatory drugs are recommended for the relief of pain associated with hand osteoarthritis (OA) but do not alter the underlying structural changes that contribute to impaired physical function. The current analysis examined the relationship of pain relief with measures of function and global rating of disease in patients with hand OA.MethodsThis was a combined analysis of 2 prospective, randomized, double-blind, 8-week, multicenter, parallel-group studies comparing diclofenac sodium 1% gel with placebo gel (vehicle) in patients with radiographically confirmed mild to moderate hand OA. Patients (n = 783) aged ≥ 40 years applied diclofenac sodium 1% gel (2 g) or vehicle to each hand 4 times daily for 8 weeks. Outcome measures included pain intensity assessed on a 100-mm Visual Analog Scale (VAS); the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) subscales for pain, stiffness, and physical function (100-mm VAS); and a global rating of disease (100-mm VAS). Change in VAS pain intensity from baseline to week 8 was categorized (<0%, 0%-<15%, 15%-<30%, 30%-<50%, 50%-<70%, and ≥ 70%) without regard to treatment and compared in each category with the mean change from baseline in each AUSCAN subindex and the global rating of disease. Pearson correlations between changes in outcome measures from baseline to week 8 were calculated.ResultsChanges in VAS pain intensity were accompanied by similar changes in AUSCAN scores and global rating of disease. Pearson correlations confirmed significant associations (P < 0.001) between change in VAS pain intensity and changes in AUSCAN pain (correlation coefficient [r] = 0.81), AUSCAN function (r = 0.75), AUSCAN stiffness (r = 0.66), and global rating of disease (r = 0.76).ConclusionsPain relief correlated with improvements in physical function, stiffness, and global rating of disease in patients with hand OA, irrespective of treatment. This suggests that pain or anticipation of pain inhibits physical function and influences patient perception of disease severity in hand OA. These results also suggest that any intervention to relieve the pain of hand OA may improve function and patient perception of disease severity, despite the absence of a disease-modifying mechanism of action.Trial registrationClinicaltrials.gov NCT00171652, NCT00171665.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.