[Improvement of the Convenience of White Petrolatum].

White petrolatum is frequently used as an oleaginous base, but has a drawback of poor usability. In this trial, white petrolatum was prepared at a lower melting point to improve its usability. Characteristic pharmaceutical values such as melting point, yield, and consistency were compared between a conventional product and ophthalmic white petrolatum. Usability was compared by administering a survey questionnaire and evaluating the comparable moisturizing effect by conductivity in humans. The melting point and yield value of the improved product were significantly lower compared with other white petrolatum products. In the survey, the improved product was rated excellent in five criteria. On a scale of 1 to 5, the average values for the five criteria for the improved product were 4.7, while the conventional product and ophthalmic white petrolatum were rated 3.0 and 3.5, respectively. No difference in moisturizing effect was observed among all petrolatums after application, from day 1 to day 14. In conclusion, the improved white petrolatum demonstrated better usability, and the moisturizing effect was equivalent to conventional product, suggesting that the use of this improved product may lead to improved adherence.

Silicate Urolithiasis during Long-Term Treatment with Zonisamide.

Silicate urinary calculi are rare in humans, with an incidence of 0.2% of all urinary calculi. Most cases were related to excess ingestion of silicate, typically by taking magnesium trisilicate as an antacid for peptic ulcers over a long period of time; however, there also existed unrelated cases, whose mechanism of development remains unclear. On the other hand, zonisamide, a newer antiepileptic drug, is one of the important causing agents of iatrogenic urinary stones in patients with epilepsy. The supposed mechanism is that zonisamide induces urine alkalinization and then promotes crystallization of urine components such as calcium phosphate by inhibition of carbonate dehydratase in renal tubular epithelial cells. Here, we report a case of silicate urolithiasis during long-term treatment with zonisamide without magnesium trisilicate intake and discuss the etiology of the disease by examining the silicate concentration in his urine.