Hydrogen peroxide (H2O2)-based tooth bleaching reagents have recently increased in popularity and controversy. H2O2 gel (3%) is used in a Nightguard for vital bleaching; transient tooth sensitivity and oral mucosa irritation have been reported. Genotoxicity and carcinogenicity have also been significant concerns. We used primary cultured normal human oral keratinocytes (NHOKs) as an in vitro model to investigate the pathological effects to mitochondria functions on human oral keratinocytes exposed to different doses of H2O2 for different durations. An MTT assay showed compromised cell viability at a dose over 5 mM. The treatments induced nuclear DNA damage, measured using a single-cell gel electrophoresis assay. A real-time quantitative polymerase chain reaction showed H2O2 induced significant increase in mitochondrial 4977-bp deletion. Mitochondrial membrane potential and apoptosis assays suggested that oxidative damage defense mechanisms were activated after prolonged exposure to H2O2. Reduced intracellular glutathione was an effective defense against oxidative damage from 5 mM of H2O2. Our study suggests the importance for keratinocyte damage of the dose and the duration of the exposure to H2O2 in at-home-bleaching. A treatment dose ≥100 mM directly causes severe cytotoxicity with as little as 15 min of exposure.

Long-term continuous exposure to potentially inappropriate medications (PIMs) can lead to adverse events in the elderly. However, the effects of long-term exposure of the elderly to PIM and the relationship between PIM and chronic diseases remain unclear. The objective of this study was to investigate the continuous use of PIMs in a community-dwelling elderly population. A cross-sectional population-based study was conducted using community pharmacy–filed dispensing records from the Hcare system. Twenty-three community pharmacies were sampled from 2013 to 2015 to obtain records of patients above 65 years-old with continuous prescriptions. PIM were identified according to the 2015 Beers Criteria. The prevalence of patients using PIM was highest in patients with co-morbid mental disorders (40.05%), followed by neurological system disorders (28.91%). Patients who were prescribed a PIM were more than three times as likely to have a mental disorder as those (odds ratio 3.16, 95% confidence interval: 3.06–3.28) with non-chronic diseases. The most prescribed PIM agents were central nervous system drugs (53.16%), and benzodiazepines (35.15%). Patients with mental disorders had the highest rate of long-term persistent PIM exposure, with benzodiazepines being the most frequently dispensed. Drug safety concerns should be closely monitored in elderly patients with the abovementioned conditions.

Taiwan offers affordable access to health care through the National Health Insurance (NHI) Program, but this increases the risk of waste of medications and pollution caused by improper disposal. This research aimed to: (1) understand methods of disposal of unused medications, and public awareness of related issues, (2) understand the sources and types of unused medications and reasons for their disposal, and (3) propose improvements to current disposal practices. Data on practices and perspectives on the disposal of medications were collected from members of the public using a questionnaire, and subjected to chi-square analysis of demographic variables. The survey found that many respondents disposed of medications inappropriately, but most believed the government should establish a return system. The majority of discarded medications came from hospitals, and were most frequently discarded because patients had forgotten to take them. Based on these findings, the study proposes that receiving stations be established across Taiwan for the safe and environmentally friendly disposal of unused medications, along with a system of monthly checks and compensation for pharmacists’ costs. The study also suggests that pharmacists strengthen medication guidance, spend more time on medication counseling, better understand the reasons for medication waste, and offer health education and advice to physicians and the public.