Kim TY, et al. - Considering the recommendation from an ASBMR Task Force for a drug holiday in certain women treated for ≥5 years with oral alendronate or ≥3 years with intravenous zoledronic acid, with reassessment 2 to 3 years later, researchers examined changes in bone mineral density (BMD) and procollagen type I N propeptide (PINP) after oral vs intravenous bisphosphonate use. They randomized women who received a mean 5 years of alendronate to placebo or continued treatment in the Fracture Intervention Trial Long-term Extension (FLEX). Outcomes revealed meaningful declines in total hip BMD and elevations in PINP among a considerable proportion of former alendronate and zoledronic acid users, 3 years after bisphosphonate discontinuation. This study suggests a more rapid offset of drug effect of alendronate than zoledronic acid despite a longer treatment course.