Days Supply Calculator
How long does a prescription pack last? Calculate days supply from total units, dose per intake, and frequency per day.
Frequently asked questions
Days supply = how many days the dispensed pack will last at the prescribed dose. UAE insurance refills are calendar-day based — typically you can refill 5-7 days before the previous supply runs out. Days supply also helps the pharmacist spot adherence problems (if a 30-day pack lasted 45 days, the patient is missing doses).
PRN doses are not taken every day — they're taken when needed (e.g. pain relief). Use the optional 'PRN factor' slider: 0.5 means the patient takes about half the maximum schedule. For chronic PRN insurance refills, regulators typically assume 50-75% of max use. Discuss with the pharmacist if the patient's actual use is much different.
Same formula. 'Total units' = total mL in the bottle, 'dose per intake' = mL per spoon/syringe, 'times per day' = frequency. A 100 mL bottle, 5 mL three times daily = 100 ÷ (5 × 3) = 6.6 days = lasts 6 full days with 5 mL leftover.
Because the last dose doesn't always come out evenly. A 30-tablet pack at 4 tablets/day = 7.5 days, meaning 7 full days + 4 leftover tablets (a half-day's supply). The calculator shows both the rounded whole days and the leftover units.
Yes — UAE insurers (Daman, ADNIC, Oman Insurance, GIG Gulf etc.) usually require 80-85% of the previous days supply to be consumed before approving a refill. So a 30-day script can refill ~5-6 days early. Beyond that the system rejects with 'too early to refill' until the consumption threshold is met.
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