Final answer:
The first action in treating a drug overdose is to ensure the patient has an adequate airway, which is crucial for maintaining breathing and allowing for further treatment steps such as naloxone administration.
Step-by-step explanation:
The FIRST thing you should do when treating a patient for an overdose of drugs is to ensure the patient has an adequate airway. This is critical as opioids, for example, can slow or even stop a person's breathing, leading to overdose deaths. The immediate action of securing the airway can ensure that the patient continues to breathe, which is vital before further assistance such as calling the poison control center or administering naloxone (Narcan), an opioid-overdose antidote, can take place.