Which substances should activated charcoal not be used with?

Activated charcoal is a substance used in emergency medical situations to absorb certain types of toxins or drugs in the gastrointestinal tract, preventing their absorption into the body. However, it is not effective for all substances, and there are certain categories where its use is contraindicated.

The correct answer pertains to its interaction with strong acids, strong alkalis, lithium, and iron tablets. These substances can cause significant damage to the gastrointestinal tract. When activated charcoal is administered in these cases, it may bind to the substances ineffectively or create a barrier that complicates the subsequent management of the patient. For example, in the case of strong acids or alkalis, the tissue damage may worsen, and charcoal could also potentially make it harder to identify the pathophysiological impact of the ingestion during advanced treatments like endoscopy.

In the case of lithium and iron, these metals can create an obstructive bezoar when mixed with activated charcoal, further complicating medical management. It’s crucial to recognize that activated charcoal does not adsorb all substances uniformly, and certain metals and corrosive agents can lead to serious complications.

This knowledge helps EMTs make informed decisions about when to administer activated charcoal and when it is safer to withhold it, ensuring optimal patient care.