Diclofenac

Overview

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) widely used in therapy for pain and inflammation. Its pharmacological activity is primarily associated with inhibition of cyclooxygenase enzymes, especially Prostaglandin-endoperoxide synthase 2 (COX-2), leading to reduced prostaglandin synthesis and downstream anti-inflammatory, analgesic, and antipyretic effects. In biomedical research, diclofenac is frequently used as a reference compound for comparing analgesic potency, COX-2 inhibition, and related pharmacological responses.

Beyond its therapeutic use, diclofenac is also an important environmental micropollutant because it is commonly detected in wastewater and surface waters. This dual role has made it a recurring subject in studies of drug efficacy, toxicology, environmental fate, and wastewater treatment. Recent research has examined diclofenac alongside compounds such as ibuprofen, indomethacin, mefenamic acid, naproxen, and (RS)-ketoprofen, both as a comparator drug in pharmacological assays and as a contaminant targeted for removal in engineered treatment systems.

Focus of Latest Publications

Recent publications on diclofenac have focused on its use as an analgesic and anti-inflammatory comparator, as well as on new delivery and monitoring approaches. In cancer pain management, one report noted that the efficacy of switching patients from prior nonsteroidal anti-inflammatory drugs to transdermal diclofenac has not been fully evaluated, highlighting interest in its role for mild cancer pain and as an adjunct to opioids in more severe pain. Another study developed a thermoresponsive, mucoadhesive in-situ nasal gel incorporating diclofenac sodium for intranasal delivery, aiming to improve bioavailability by bypassing first-pass metabolism, increasing mucosal retention, and minimizing irritation.

Several studies examined diclofenac in formulation and drug-delivery contexts. A cationic bionanocomplex based on aryl-modified chitosan derivatives was evaluated for controlled release of diclofenac sodium alongside other drugs; diclofenac showed the fastest release from the system, and kinetic modeling suggested non-Fickian diffusion. In a separate comparison of anti-inflammatory agents, diclofenac sodium served as a reference COX inhibitor in the in vitro and in silico assessment of multi-functionalized pyrimidines, where the new compounds outperformed diclofenac in COX-2 selectivity and in some cases in 5-LOX, IL-6, and reactive oxygen species-related assays. Diclofenac sodium was also used as a benchmark in a phytochemical study of Diospyros sylvatica leaves, where the plant fraction showed analgesic activity but remained less potent than diclofenac sodium in the acetic acid-induced writhing model.

Beyond therapeutic development, diclofenac has appeared in safety and environmental studies. In calves with bovine respiratory disease complex, diclofenac sodium administered with tilmicosin was associated with elevated cardiac biomarkers, suggesting early subclinical myocardial injury and additive hepatocellular and myocardial stress, while creatinine and hematological parameters were unchanged. In an urban river monitoring study, diclofenac was detected as a localized spike along the Ciliwung River, consistent with point-source inputs from healthcare or residential discharge. Diclofenac was also among the compounds that produced comparable responses in a graphene-based electrochemical platform for detecting oxidizable contaminants in water, supporting its relevance in broader pharmaceutical pollution screening.

Key Publications

NEWJan Efficacy of Switching from Prior Nonsteroidal Anti-inflammatory Drugs to Transdermal Diclofenac in Cancer Pain Management. (In vivo (Athens, Greece), 2026, PMID 42379803): "The efficacy of switching from prior NSAIDs to transdermal diclofenac in patients with cancer has not been fully evaluated, however."
NEWJun Multi-Class Pharmaceutical Profiling Along an Urbanization Gradient in a Tropical Megacity River: Evidence for Cumulative Loading and Limited Attenuation. (Bulletin of environmental contamination and toxicology, 2026, PMID 42301429): "Localized spikes for diclofenac and metronidazole suggest point-source inputs from healthcare or residential discharge."
Jun An Integrated Pharmacological Evaluation and GC-MS/MS-Guided Metabolite Profiling of Diospyros sylvatica Roxb. Leaves Revealing Analgesic, Antioxidant, and Antidiabetic Activities. (Chemistry & biodiversity, 2026, PMID 42218796): "The n-hexane fraction showed the strongest analgesic activity with 50.40% writhing inhibition compared to diclofenac sodium (69.77%)."
May Extraction, development, and ex-vivo evaluation of thermoresponsive mucoadhesive in-situ nasal gel incorporating Lablab purpureus mucilage and Pluronic F127 for enhanced intranasal delivery of Diclofenac Sodium. (Drug development and industrial pharmacy, 2026, PMID 42107051): "This study aimed to develop and evaluate a thermoresponsive, mucoadhesive in-situ nasal gel using Lablab purpureus mucilage and Pluronic F127 for intranasal delivery of Diclofenac Sodium to enhance bioavailability by bypassing first-pass metabolism, improving mucosal retention, and minimizing irritation."
May Graphene-Based Electrochemical Sensors for the Determination of Pharmaceutical- and Agricultural-Based Emerging Contaminants in Water. (Analytical chemistry, 2026, PMID 42060697): "Under optimized electro-Fenton (EF) conditions, additional ECs—including diclofenac, ibuprofen, glyphosate, and estradiol—showed comparable responses, demonstrating broad applicability independent of molecular structure."
May Effects of diclofenac sodium and tilmicosin on cardiac biomarkers in calves with bovine respiratory disease complex. (Acta veterinaria Hungarica, 2026, PMID 42018377): "This study aimed to evaluate the cardiotoxic potential of diclofenac sodium (DKFS) and tilmicosin (TIL), administered individually or in combination, in calves affected by bovine respiratory disease complex (BRDC)."
May Development of a cationic bionanocomplex from N-aryl-chitosan derivatives for controlled drug release. (Carbohydrate polymers, 2026, PMID 41832027): "...for the controlled release of diclofenac sodium, fluorescein sodium and tetracycline."
Jun Design, synthesis, in vitro, and in silico evaluation of multi-functionalized pyrimidines as potential multitarget-directed anti-inflammatory agents. (Bioorganic chemistry, 2026, PMID 41806609): "...with comparisons made to the well-known COX inhibitors celecoxib and diclofenac sodium."
May Synthesis, characterization, and nanoparticle formulation and evaluation of rosuvastatin-curcumin conjugate for atherosclerosis management. (Bioorganic chemistry, 2026, PMID 41633290): "The conjugate also exhibited potent COX-2 inhibition (84.62±1.18% at 200 μg/mL), comparable to diclofenac sodium, supported by molecular docking interactions with key residues (Arg120, Ser530, Tyr355)."