(HealthDay)—An opioid supply for seven or fewer days might be sufficient for most patients seen in primary care settings for acute pain who appear to need opioid analgesics, according to research published in the Feb. 15 issue of the U.S. Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.

Mallika L. Mundkur, M.D., from the U.S. Food and Drug Administration in Silver Spring, Maryland, and colleagues used a 2014 database of commercial claims to identify 176,607 patients filling an opioid analgesic prescription for 10 acute pain conditions in a primary care setting. Based on the initial number of days supplied, the probability of obtaining a refill was estimated.

The researchers found that 7.6 percent of patients filled an opioid analgesic prescription, with variance based on condition (3.5 percent for headache to 27.6 percent for dental pain). The median index prescription filled ranged from four to seven days, 20 to 30 tablets or capsules, and 100 to 155 morphine milligram equivalents. Of those filling an initial opioid prescription, 17.8 percent obtained at least one refill in the 30 days after the index prescription. The probability of obtaining an opioid analgesic prescription refill for nine of 10 conditions was <25 percent for patients who received an initial seven-day supply.

“Treatment strategies should account for patient- and condition-specific characteristics, which might reduce or extend duration of benefit from opioid analgesic therapy,” the authors write.