What is the difference between active and inactive ingredients in a product?

Answer 1

Active ingredients are usually drugs. They are usually over-the-counter drugs, meaning that they are commonly approved drugs that do something. In Selsun Blue shampoo, the active ingredient is selenium sulfide. This compound kills microorganisms that cause dandruff. Inactive ingredients are all kinds of detergents and coloring agents that don't do any thing.

Answer 2

An active ingredient is defined as the compund that has a specific purpose or a specific job. For example tinactin foot spray has an active ingredient, which is tolnaftate. The inactive ingredients would be the alcohol, talc and and propylene glycol etc. The inactive ingredients do not contribute to what the product is meant to do which is kill fungus, the tolnaftate does that.

Another example is an ibuprofen tablet. The active ingredient is the ibuprofen, it helps to relieve inflammation. The inactive ingredients would be the fillers put into the tablet. They do not help to relieve inflammation, they just help to keep the pill together when they put it into the pill press.