Parenteral Controlled Substances

October 18, 2023

A controlled substance is a drug or chemical whose manufacture, possession and use is regulated by the government. Drugs and other substances classified as controlled substances under the Controlled Substances Act (CSA) are divided into five schedules (schedule I, II, III, IV, or V).

Substances are placed in their respective schedules based on whether they have a currently accepted medical use in treatment in the United States, their relative abuse potential, and likelihood of causing dependence when abused. An updated and complete list of the schedules is published annually in Title 21 Code of Federal Regulations (C.F.R.) §§1308.11 through 1308.15.

Parenteral drug administration refers to drugs given by routes other than the digestive tract. This route is used for medication administration when a rapid drug effect is desired; a precise serum drug level is needed; or when drugs are unstable or poorly absorbed in the gastrointestinal tract.

The four types of parenteral routes include:

• Intravenous (IV)-Into a vein
• Intramuscular (IM)-Into a body of a muscle
• Subcutaneous (SQ)- Under the skin
• Intrathecal (IT)- Into the subarachnoid space around the spinal cord.

As stated in 2023 CPT E/M coding guidelines, when determining the level of risk, a parenteral controlled substance is considered a high-level risk.

Here are some helpful tips to follow when determining if the scenario is high risk:

• Determine if the drug/substance is a “Controlled” substance. Check the list of Controlled Substances via the FDA website. If the drug/substance is a Schedule I, II, III, IV, or V then the drug/substance is considered “controlled.”
• Determine whether the drug/substance was administered parenterally.
• If the drug/substance was administered parenterally and the drug/substance is considered “controlled,” a high level of overall Risk may be credited toward the level of medical decision-making.
• If the drug/substance administered is not a controlled substance or was not administered parenterally or was not ordered to be administered parenterally, then a high level of overall risk may not be credited toward the level of medical decision making for parenterally controlled substances. The medical record will need to be reviewed for other indications to determine the level of overall risk.



Kimberly Stillings, RHIT, CPC, CPMA
External Auditor | Excite Health Partners




AMA CPT 2023 Professional Edition

Title 21 Code of Federal Regulations (CFR) 21 CFR §1308)