The neuropeptide oxytocin (OT) modulates functioning of the hypothalamic-pituitary-adrenal (HPA) axis and regulates a range of social processes. Clinical studies have used intranasal OT administration to treat symptoms arising from a number of psychiatric disorders including autism, schizophrenia, and depression. Most of this research, however, has been based on single dose treatments of OT in younger adult populations. The present study examined the impact on the health and psychological well-being of a 10-day OT administration in an older adult population. Residentially housed older adults (N = 41, mean age of 80) were enrolled in a randomized, double-blind, placebo-controlled study. Participants received 40 IU intranasal OT or placebo for 10 consecutive days. No changes in mood or cardiovascular states were observed across the 10-day period. Repeated-measures ANOVAs showed that dispositional gratitude improved for the OT infused participants, although gratitude declined for placebo controls over the 10 days (p = .015). Those in the OT condition did not report a decline in physical functioning over time as was observed in the placebo condition (p = .05), and also reported less fatigue compared with controls (p = .03). No significant adverse events were reported throughout the entirety of the study, indicating that OT can be safely used with older adults.