1 gram of activated charcoal has a surface area of 500 square meters due to the microscopic pores in the carbon. Carbon binds very well to many toxins and prevents their absorption by the digestive tract. It also prevents other toxins from having their normal effect on the human body by interrupting their normal chemical action. However, it is counter-productive and harmful if administered in the lungs or where the suspected toxin is an acid, alkali (such as drain cleaner) or petroleum product.
Activated charcoal is generally stored in water in a standard dose of 12 grams. A standard dose is 1 gram of activated charcoal per 1 kilogram of body weight.