Every 8 hours, in short
Every 8 hours (written q8h on prescriptions) means 3 doses in 24 hours, spaced evenly around the clock, including overnight. A common every 8 hours schedule is 7am, 3pm and 11pm.
Every 8 hours schedules
Each row is the same 8-hour spacing, shifted to fit a different day. Pick the one closest to when you wake up, or set your own times in the calculator above.
| Schedule | Works well if you |
|---|---|
| 6am, 2pm, 10pm | wake up at 6am and go to bed around 10pm |
| 7am, 3pm, 11pm | wake up at 7am and go to bed around 11pm |
| 8am, 4pm, 12am | wake up at 8am and go to bed around midnight |
Planning every 8 hours around sleep
If you sleep 8 hours or less, you can usually keep all three doses out of the night: take the first dose when you wake up and the last one at bedtime, 16 hours later. If you sleep longer than 8 hours, one dose will land during your sleep, and it's worth asking your pharmacist whether that dose can move.
How many doses in a course?
| Course length | Doses (1 every 8 hours) |
|---|---|
| 5 days | 15 |
| 7 days | 21 |
| 10 days | 30 |
| 14 days | 42 |
The total is the same whatever time of day you start. Your pharmacist can confirm how many doses your prescription should have.
Common questions
How many times a day is every 8 hours?
Every 8 hours is 3 times a day, because 24 hours divided by 8 is 3 doses. A typical schedule is 7am, 3pm and 11pm.
Is every 8 hours the same as three times a day?
Not always. Three times a day (TID) usually means three doses spread across your waking hours, often with meals. Every 8 hours (q8h) means evenly spaced doses, including overnight. If you're not sure which your prescription means, ask your pharmacist.
Do I have to wake up at night to take medicine every 8 hours?
Often not. If you sleep 8 hours or less, you can take the first dose when you wake up and the last at bedtime, so none of the three land at night. If a dose still falls while you're asleep, ask your pharmacist how strict the timing needs to be for your medication.
How many tablets is 1 tablet every 8 hours for 7 days?
21 tablets, which is 3 a day for 7 days. A 10 day course is 30 tablets.