You are here

Inactive ingredients, the unsung players in medicines

30 April 2020

Medicine ingredients are like players in a soccer team. The star player (active ingredient) might kick the winning goal, but often they can only do it with the help of other players (inactive ingredients, also called excipients).

The active ingredient in a medicine enables the medicine to do what it claims. Examples of active ingredients are paracetamol in some pain relief medicines and atorvastatin in some cholesterol-lowering medicines.

An inactive ingredient is any non-active ingredient in a medicine. These might mask a bitter taste or preserve a medicine until its expiration date. Some inactive ingredients are essential for a medicine to function as intended. For instance, an active ingredient that does not dissolve easily might use an inactive ingredient to help the body absorb it.

Inactive ingredients are the unsung but important ingredients in medicines. For most people, they are safe, provided the medicine is used according to the label instructions.

However, people with allergies or sensitivity to certain substances should be aware of their medicines' inactive ingredients.

How do I find out about my medicine's inactive ingredients?

The most important information about your medicine, such as the active ingredients or common allergens, will always be on the medicine label. In the case of prescription medicines and some over-the-counter medicines this can be included in the consumer medicines information (CMI) leaflet.

If the names of inactive ingredients are not listed on the medicine label, you can instead find this information by searching for the medicine through our TGA website's search function.

On the top right of every page on this website, including this one, there is a box that says "Search TGA". Search for either the medicine's name or AUST number (found on the label) to find the medicine's Australian Register of Therapeutic Goods (ARTG) summary.

The first search results are always links to ARTG summaries in PDF file format. An ARTG summary has detailed information about the medicine, including the names of active and inactive ingredients in the medicine's formulation.

Some information is not available in the ARTG summary. While the ARTG summary lists ingredients, it will not say whether an ingredient is natural or synthetic. The ARTG summary does not include information about substances used in the manufacture of the medicine or substances that are components of ingredients (such as caffeine present in a herbal extract). For information like this, contact the medicine company using the details on the medicine label.

For further information about ingredients, visit our page What ingredients are in my medicine?

Scientific and common names for ingredients

ARTG summaries use scientific names for ingredients, which may be different from the common names generally in use. Below is a list of common names for some ingredients that may be of interest to people with allergies or sensitivities.

Common name Scientific name




Sesamum indicum

Soya bean

Glycine max


Juglans cinerea, Juglans nigra or Juglans regia


Prunus dulcis

Parabens (widely used preservatives)

hydroxybenzoates (many variants)

Polyethylene glycol (PEG)


The ARTG summary will not always tell you what an ingredient is made from. For example, lecithin is often made from soy, while glucosamine may be made from seafood. The ARTG summary will list the ingredient names lecithin or glucosamine, but not their sources.

Where the source of an ingredient is a common allergen, like soy or seafood, the medicine label will include a warning.

Talk to your doctor or pharmacist about health decisions

If you have concerns about the ingredients in your medicines, talk to your doctor or pharmacist. Their advice can guide your decisions about medicines.

For more information about allergens, consult our page Allergies and medicines.

Now, you know how to find out more about the inactive ingredients in your medicines… and that is more information to help you kick your health goals.