Patient behavior patterns regarding prescription refills.

This study was conducted to examine the association between drug price, drug category, duration of coverage of the original prescription, units prescribed per day, and a patient's failure to obtain authorized refills of prescription medication. A two-stage sampling of pharmacies and prescriptions yielded a total sample of 1,058 prescriptions. The Drug Possession Ratio (DPR), defined as the ratio of number of days of medication dispensed to number of days of medication prescribed, was significantly related to drug price and drug category (p less than 0.05). The highest DPR was associated with the most expensive medication. Tranquilizers, antidepressants, and sedative hypnotics exhibited high DPR, while antihistamines and decongestants exhibited low DPR.