Blog Date 29 March, 2023

What are Active Pharmaceutical Ingredients (APIs) & Excipients?

What are Active Pharmaceutical Ingredients (APIs) & Excipients?

Any drug formulation is composed of two components or aspects. The first is the actual API or Active Pharmaceutical Ingredients, which is the central ingredient. The second is known as an excipient, which is the inactive ingredient. Excipient serves as a medium for conveying the active ingredient. The Active Pharmaceutical Ingredient (API) forms the most vital part of every formulated product, and is an important part of the whole pharmaceutical industry.

The Active Pharmaceutical Ingredient Industry is the organ by which active pharmaceutical ingredients are manufactured from raw materials through both chemical and physical means. Depending on the complexity of the molecule required, synthesis of APIs might need multi-step complex chemistry utilizing a range of processing technologies. Indian companies manufacture 85% of the active pharmaceutical ingredients (API) required by the country and account for 90% of the pharmaceutical exports. The Indian pharmaceutical sector has made the country self-sufficient in almost all the 300 essential drugs through indigenous process technology.

Active Pharmaceutical Ingredient:

 Any substance or mixture of substances intended to be used in the manufacture of a drug (medicinal) products and that, when used in the production of a drug, becomes an active ingredient of the drug product. Such substances are intended to furnish pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure or function of the body.

APIs include substances manufactured by processes such as

(1) Chemical synthesis

 (2) Fermentation

 (3) Recombinant DNA or other biotechnology methods

(4) isolation/recovery from natural sources or any combination of these processes.

 API Intermediate:

 A material produced during steps in the synthesis of an API that must undergo further molecular change or processing before it becomes an API.

Drug Product:

A finished dosage form, for example, a tablet, capsule or solution that contains an active pharmaceutical ingredient, generally, but not necessarily, in association with inactive ingredients (excipients).

Pharmaceutical Excipient:

An excipient is pharmacologically inactive substance formulated along with the active pharmaceutical ingredient of a medication or drug product.

Examples of excipients include fillers, extenders, diluents, wetting agents, solvents, emulsifiers, preservatives, flavors, absorption enhancers, sustained-release matrices, and coloring agents.

Fine chemicals:

 Fine chemicals are complex, single, pure chemical substances, produced in limited quantities. They are generally produced in multipurpose plants by multistep batch chemical or biotechnological processes.


Active Pharmaceutical Ingredients and Excipient Examples

Raw Materials


API/ Excipient

Organic Substances(Synthetic)



Mixture Of organic Substance

Polyethylene glycol, Soya Oil


Mixture Of Inorganic Substance



Gases & Liquids

Oxygen, Water


Radio Active Substance



Biological Macromolecules



Products of Human and Animal Origin

Human Plasma


Plant Materials

Herbal Drugs


API production is a highly sophisticated, technically demanding process and which is accomplished by chemical synthesis or biochemical methods. Active pharmaceutical ingredients are first obtained in the crude state. Subsequent production operations convert the crude material to the final API that meets the pharmacopoeial and/or similar requirements. Pharmaceutical manufacturing occurs in two general steps. First, raw materials are converted into Active Pharmaceutical Ingredients (APIs). The second step in pharmaceutical manufacturing is the final formulation of the drugs. Final formulations of API employs three major types of processes: organic chemical synthesis, fermentation and biological and natural extraction.


Simson Pharma Limited is a research-based organization that specializes in manufacturing/ exporting/ supplying of API, reference materials& Isotope Labelled Compounds of Pharmaceutical use, Phytochemicals, Agrochemical standards, Environmental use, and Food and Beverage standards.

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