Concept:
ICU patients are critically ill and often require urgent and high-risk medicines.
Step 1: ICU drug use.
ICU drugs may include emergency medicines, life-saving drugs, sedatives, vasopressors, and injectable preparations.
Step 2: Why special control is required.
Wrong drug, wrong dose, or delay in ICU can lead to serious harm.
Step 3: Importance of monitoring.
Special control ensures proper storage, availability, dosing, and safe administration.
Step 4: Final answer.
Hence, ICU drug distribution requires special control because of high-risk and emergency drugs.
\[
\boxed{\text{High-risk and emergency drugs}}
\]