Rapid opioid dose escalation, possibly caused by tolerance, has been observed in some patients on daily opioid therapy, although clinically identifiable characteristics of these patients are unknown. In this retrospective chart review of 206 patients, we examined whether the age of the patient was related to opioid escalation. Initial starting doses of long-acting opioids were similar in younger patients (< or =50 yr; 49 +/- 3 mg/d oral morphine-equivalent dose) versus older patients (> or =60 yr; 42 +/- 3 mg/d). Younger patients reached a maximum dose of 452 +/- 63 mg/d over 15.0 +/- 1.3 mo, whereas older patients achieved a maximum dose of 211 +/- 23 mg/d over 14.4 +/- 1.5 mo (P < 0.0001). At the last clinic visit, younger-patient dosing averaged 365 +/- 61 mg/d, with older patients averaging 168 +/- 18 mg/d (P < 0.0001). Only older patients demonstrated a reduction in visual analog scale scores from start of opioid therapy until discharge from the clinic (6.9 +/- 0.3 to 5.6 +/- 0.3; P < 0.01). These clinical data suggest that age is an important variable in opioid dose escalation. Although factors other than opioid tolerance can result in dose escalation, it is possible that older patients may have a reduced rate of tolerance development.