What does q4h indicate in dosing intervals?

What does q4h indicate in dosing intervals?

• A. Every 8 hours
• B. Twice a day
• C. Every 6 hours
• D. Every 4 hours

Answer: (D)

Dosing interval abbreviations use the letter q to mean “every,” and the number that follows is the number of hours between doses. So q4h means give the dose every 4 hours. This is different from other patterns: q8h would be every 8 hours, q12h (often written as twice daily or bid) is every 12 hours, and q6h would be every 6 hours. In practice, a 4-hour interval keeps drug levels more constant for medications with short action or narrow therapeutic windows, and it may require around-the-clock dosing depending on the drug and animal’s needs.

Dosing interval abbreviations use the letter q to mean “every,” and the number that follows is the number of hours between doses. So q4h means give the dose every 4 hours. This is different from other patterns: q8h would be every 8 hours, q12h (often written as twice daily or bid) is every 12 hours, and q6h would be every 6 hours. In practice, a 4-hour interval keeps drug levels more constant for medications with short action or narrow therapeutic windows, and it may require around-the-clock dosing depending on the drug and animal’s needs.