Formulation and Evaluation of Topical Meloxicam Emulgels

Abstract

Background: Meloxicam is one of the non-steroidal anti-inflammatory drugs (NSAIDs) and is commonly used for the symptomatic treatment of pain and inflammation associated with rheumatic diseases such as osteoarthritis. Meloxicam and other NSAIDs are predominantly available as oral dosage forms. In the recent past, topical dosage forms of NSAIDs are on the rise especially for management of chronic conditions, as they have reduced gastrointestinal, cardiovascular and other systemic side effects associated with oral medications. Consequently, they have resulted in improved patient compliance. From a survey of literature to date, there is no topical meloxicam product in the global market, whether as a gel or as an emulgel. This study therefore sought to formulate and evaluate emulgels of meloxicam for topical application, as an alternative product for management of rheumatic diseases. Methods: This research study employed a 32 factorial design and utilized both quantitative and qualitative approaches. Carbopol 934 and menthol were the two factors under study as gelling agent and penetration enhancer, respectively. The Design Expert® software was used to analyze their relationship with four responses namely viscosity, spreadability, cumulative drug permeation at 1 h and cumulative drug permeation at 8 h. The software was also used to decrypt an optimized formulation. Drug excipient compatibility studies were conducted using fourier transform infrared spectroscopy. Results and Discussion: Meloxicam active pharmaceutical ingredient and excipients used in the emulgels were found to be compatible. All formulations were translucent, homogenous and with no observable grittiness or phase separation upon visual examination. Their pH was between 5.7 (F7) and 6.5 (F2), viscosity between 20426 mPa.s (F1) and 42336 mPa.s (F8), spreadability between 7.0 cm (F8) and 9.9 cm (F10) and the percentage drug content was between 90.7 (F7) and 109.9 (F9). The order of percentage cumulative drug permeation after 1 h and after 8 h from the highest to the lowest was: F11>F10>F3>F2>F1>F9>F6>F5>F8>F4>F7 and F11>F10>F3>F2>F1>F6>F5>F9>F8>F4>F7, respectively. Conclusion: This study has shown that it is possible to formulate meloxicam emulgels that have high pharmaceutical quality and are pharmacologically active. Further optimization could potentially provide a safe and efficacious alternative for symptomatic treatment of pain and inflammation associated with rheumatic diseases as well as other inflammatory conditions.