Which of the following is NOT a common type of medication order?

In the context of medication orders, a PA order, which stands for prior authorization order, is less commonly recognized as a standard type of medication order compared to the others listed.

Standing orders are commonly used in healthcare settings to allow nurses, corpsmen, or other healthcare professionals the authority to administer medications as outlined in the standing order protocol without needing to consult a physician for every instance. These are often used for routine medications that are given in a consistent manner.

Single orders refer to medications that are prescribed to be given once at a specified time. This is a straightforward approach frequently utilized for one-time treatments or doses.

Stat orders signify that a medication should be administered immediately, often used in emergency situations where immediate action is critical for patient care.

Given that a PA order involves additional administrative steps that pertain to insurance and approval processes rather than direct medication administration in patient care, it stands out from the other options as not being a common type of medication order encountered in clinical practice.