Development, physicochemical evaluation, and in vivo permeation studies of topical formulations containing 0.1% tacrolimus

Abstract The objective of this paper was to develop and evaluate two semi-solid pharmaceutical forms containing 0.1% tacrolimus: cream (CRT01) and gel (GLT01). For the evaluation of physicochemical stability, at times 0, 30, 60 and 90 days, at 23°C and at 40°C, High Performance Liquid Chromatography coupled with a Diode Array Detector (HPLC-DAD) was employed. This method was developed and validated for tacrolimus quantification. The occlusivity test and skin permeation assay were also performed, using an animal model (Wistar rats), and the CRT01 and GLT01 were compared to the 0.1% tacrolimus ointment (PFU01) obtained from the University Pharmacy, Federal University of Rio de Janeiro, Brazil. CRT01 and GLT01 presented a homogeneous aspect and consistency adequate for topical products, along with sensory characteristics above PFU01. They also presented adequate physicochemical stability for 90 days and a lower occlusive effect than PFU01 (p<0.05). CRT01 showed greater affinity for the skin when compared to PFU01 and GLT01, with low systemic absorption. The CRT01 semi-solid formulation was considered the most adequate one to treat patients with atopic dermatitis or other dermatologic inflammatory diseases, promoting rational use of tacrolimus

Algae Metabolites as an Alternative in Prevention and Treatment of Skin Problems Associated with Solar Radiation and Conventional Photo-protection

Abstract The histological structure and biochemistry of the skin is affected by solar radiation having adverse effects ranging from sunburns, premature aging that includes wrinkles, spots, dryness, and loss of collagen to cancer development. The skin has defense mechanisms to prevent damage caused by radiation, but when radiation exposure is excessive these mechanisms are not strong enough to protect the skin. The use of sunscreen is the most common practice of photo- protection. The active ingredients of these cosmetic protective formulations are generally from synthetic origin and have presented several drawbacks at the level of photo-stability, systemic absorption and can generate contact and photo-contact dermatitis. This review illustrates skin solar radiation problems, common sunscreen ingredients limitation and mentions how algae can be an alternative according to studies that have evaluated the photo-protective potential of extracts and compounds isolated by different techniques.

Systemic absortion and adverse effects of topical ocular use of ketorolac tromethamine and sodium diclofenac in New Zealand rabbits for 90 days / Absorção sistêmica e efeitos adversos do uso tópico ocular por 90 dias de cetorolaco de trometamina e diclofenacode sódio em coelhos da raça Nova Zelândia

The effect of the systemic absorption of 0.1% diclofenac sodium (DS) eyedrop was compared to that of 0.5% ketorolac tromethamine (KT) in female New Zealand white rabbits treated on both eyes three times a day for 90 days. The rabbits were divided in three groups of six animals (n= 18): KT group, DS group, and control (Co) group, in which saline (0.9% NaCl) solution was instilled. Water and food consumption were measured daily, clinical examination was performed weekly, and blood samples were collected every 30 days for laboratory examination. The plasma was analyzed for the presence of KT and DS by solid-phase extraction (SPE) associated with mass spectrometry (MS). Systemic absorption of these drugs was confirmed by SPE-MS, allowing their separation and identification in the plasma. At the end of the treatment, the animals were euthanized and necropsied, and no macroscopic or microscopic changes were found. This observation confirmed the laboratory results, which were within normal reference standards for the species. According to the results obtained, it can be concluded that treatment with eyedrops containing KT and DS for 90 days in healthy rabbits does not cause adverse systemic effects.(AU)

Comparou-se o efeito da absorção sistêmica do colírio de diclofenaco de sódio 0,1% (DS) em relação ao de cetorolaco de trometamina 0,5% (CT) em coelhas da raça Nova Zelândia, tratadas nos dois olhos, três vezes ao dia, por 90 dias. As coelhas foram separadas em três grupos de seis animais (n=18): grupo CT, grupo DS e grupo controle (Co), no qual foi instilada solução fisiológica (NaCl 0,9%). Os consumos de água e ração foram mensurados diariamente, os exames clínicos foram realizados semanalmente e o sangue foi coletado a cada 30 dias para realização de exames laboratoriais. O plasma foi analisado para detectar a presença de CT e DS por extração em fase sólida (SPE) associada à espectrometria de massas (MS). A absorção sistêmica desses fármacos foi confirmada por SPE-MS, permitindo sua separação e identificação no plasma. Ao final do tratamento, os animais foram eutanasiados e necropsiados, e não foram encontradas alterações macroscópicas ou microscópicas. Essa observação confirmou os resultados laboratoriais, que estavam dentro dos padrões de referência para a espécie. De acordo com os resultados obtidos, pode-se concluir que o tratamento com colírio contendo KT e DS, por 90 dias, em coelhos saudáveis, não causa efeitos adversos sistêmicos.(AU)