Final answer:
The next dose of medication should be administered at 0100 hours (1:00 AM) following a dose given at 1900 hours (7:00 PM) when the medication is prescribed to be taken every six hours (Q6h).
Step-by-step explanation:
If a patient must receive a drug Q6h (every six hours) and the patient receives one dose at 1900 hours (or 7:00 PM), we must add 6 hours to this time to determine the time of the next dose. Adding 6 hours brings us to 0100 hours (or 1:00 AM) on the following day. Therefore, the patient should receive the next dose of medication at 0100 hours.
In military time, a patient who receives a drug every 6 hours would need to receive it at 0100, 0700, 1300, 1900, and so on. Starting at 1900, the next dose would be administered at 0100, which is 6 hours after the previous dose.