What are excipients?  

Excipients (or inactive ingredients) are ingredients used to transform active compounds into dosage forms suitable for administration. All pharmaceutical or nutritional products – whether they are tablets, capsules, liquids, vaccines or other – contain excipients. It is simply not possible to formulate these products without using binders, fillers, stabilizers and/or disintegrants. 

Pharmaceutical excipients are substances other than the active pharmacological ingredient (API) which are included in the manufacturing process. Excipients are added to support the manufacturing process, to protect, support or enhance stability, or for bioavailability or patient acceptability.  

Choosing the right excipients is a key determinant of the quality and functionality of a pharmaceutical product.  

Why are excipients important in a drug product?  

Excipients are the “unsung heroes” of the pharma industry. They are key in drug manufacturing for several reasons. Some excipients comprise the product's delivery system. These convey the active ingredient to the part in the body where the drug is intended to be applied.   

Other excipients ensure the drug from being released too early in places where it could damage and create gastric irritation or stomach upset.   

There are also excipients that help a medicine to disintegrate into small particles to reach the blood stream more quickly while others protect the drug product's stability so it will be at maximum effectiveness at time of use.   

Although technically "inactive" from a therapeutic perspective, pharmaceutical excipients are key and essential elements of medicines. In many products, whether tablets, capsules, inhalers, or vaccines, excipients make the bulk of the total dosage form.