Formulation and Stability of a 1% Clarithromycin-Based Topical Skin Cream: A New Option to Treat Buruli Ulcers?

There are more than 170 known species of non-tuberculous mycobacteria, and some are responsible for serious diseases in people infected with them. One of these is Buruli ulcers, a neglected tropical disease endemic in more than 33 countries and caused by Mycobacterium ulcerans, which infects skin tissue. Treatment consists of a long-term regimen combining the use of oral rifampin with another anti-tuberculosis drug (e.g., clarithromycin). Patients in these countries face difficulties in accessing and adhering to this therapy. This study investigates the feasibility of formulating stable, optimized clarithromycin as a topical cutaneous cream. The cream was formulated, and its stability was evaluated under different storage temperature conditions and using a stability indicator method. The results showed that the clarithromycin cream was stable for at least 60 days, even at extreme temperatures (40 °C). In conclusion, the data presented here demonstrate the stability of a new form of topical cutaneous clarithromycin, which may offer a new approach to the treatment of Buruli ulcers and clarithromycin-sensitive infections.

Stability of 10-mg/mL and 50-mg/mL ketamine oral solutions.

PURPOSE: Ketamine is an anesthetic agent commonly used for the induction of anesthesia. Ketamine is also given to control pain, for treatment of posttraumatic stress disorder, and to induce bronchodilation in refractory asthma. Moreover, ketamine therapy is gaining ground as an intervention for patients with treatment-resistant depression and individuals who have depression with serious suicidal ideation. Recently, the drug has been used to disrupt maladaptive reward memories in individuals with harmful alcohol consumption behaviors. The stability of 10-mg/mL and 50-mg/mL ketamine solutions stored at ambient and refrigeration temperatures was assessed over 90 days. METHODS: Three batches of 10-mg/mL and 50-mg/mL ketamine solutions were stored for 90 days under two temperature conditions (2°C-8°C and 22°C-25°C) in amber plastic bottles. Chemical stability was assessed using a stability-indicating high-performance liquid chromatography assay. At each study time, visual inspection and pH assessments of ketamine concentration and pH were conducted. RESULTS: For all solutions tested at each condition, the ketamine concentration remaining was at least 98% of the initial concentration over 90 days of storage. Throughout the study period, solution pH remained stable and the color and odor of the suspensions remained unchanged. CONCLUSION: Extemporaneously compounded 10-mg/mL and 50-mg/mL oral solutions of ketamine prepared in a flavored suspending excipient and stored in amber polypropylene plastic bottles were stable for at least 90 days at both ambient and refrigeration temperatures.