Which abbreviation means administration should occur at once?

• A. at once
• B. sig.
• C. s.o.s
• D. stat

Answer: (C)

In medication orders, urgency is signaled by the abbreviation for “statim,” meaning administer immediately without delay. That’s why the standard, widely recognized directive for rushing a dose is stat. The other terms have different meanings or usages: “at once” is a plain instruction but not a formal shorthand; “sig.” (signa) refers to directions for how the dose should be taken, not the timing; and “s.o.s.” is not a reliable, universally recognized abbreviation for immediate action and can be ambiguous. Because patient safety hinges on clear, unambiguous timing, the term that best communicates immediate administration is stat.