Excipients: The Critical Ingredients for Pharmaceutical Products

Excipients are inactive ingredients that help deliver and process the active pharmaceutical ingredients and often find critical roles in final pharmaceutical products. Excipients have a more significant role in final product usefulness.

Based on Final Product Specifications and usage requirements, one needs to choose the suitable excipients and the correct amount for the quality and functionality of a pharmaceutical product.

Excipient comes in many forms. Based on the preference for solid dosage forms, as seen in the consumer market, many types of excipients used in tablets and capsules are available. Some standard classes of excipients include fillers, binders, disintegrants, lubricants, flow aids, and sustained release agents. These excipients can then be divided into two general groups – excipients that help process the drug and excipients that help deliver the active pharmaceutical ingredient (API) inside the body.

In many cases, the API in a solid dosage makes up a small percentage of its total mass. It’s challenging to consume a very low milligram dosage of API without excipients, and this is where fillers and diluents come into play. Fillers act as bulking agents, increasing the size of the finished products and making it much easier for the final dosage form. Fillers can also affect the delivery of the drug within the body. They can be soluble or insoluble, and depending on the purpose of the drug, a filler can increase or decrease the dissolution time of the API. For example, insoluble microcrystalline cellulose would help a delayed-release drug, while soluble lactose could correspond better with an immediate-release drug.

Disintegrants are also used to increase the rate of dissolution of a tablet. When disintegrants enter the body and make contact with gastric fluid, they expand and help break up the tablet, increasing the amount of API exposed to the gastric fluid in a shorter time frame, allowing it to dissolve faster and be available for absorption sooner. Using a soluble filler with a disintegrant may be the basis for an immediate-release drug. The formulations need disintegration and dissolution testing requirements to obtain the desired dissolution requirement.

Other excipients help make the manufacturing process run more smoothly and help maintain manufacturing equipment such as tablet presses and tooling. These types of excipients are helpful for the unfavourable characteristics of the API. Binders, often used with fillers, help keep ingredients in solid dosage form together. APIs cannot be easily compressed independently; however, binders can help improve their compressibility. APIs flow poorly through processing equipment because they generally have poor processing characteristics. Excipient flow aids like colloidal silicon dioxide allows the formulation to flow across equipment surfaces more efficiently. Lubricants then help eject the compressed tablets out of the die of a tablet press.

Each excipient has a different functional role, and several considerations go into choosing the right combination and grades. Some excipient and API combinations can be incompatible. For example, magnesium stearate, a lubricant, should not be used with strong acids or aspirin products. Though much of the incompatibility information is available, excipient compatibility studies are helpful to ensure that the API remains stable and no unwanted reactions occur.

Decision-making is complex, with many options available for selecting suitable excipients. The experts at Clyzo help you choose the right choice for your excipients. Clyzo also offers regulatory services that give you comprehensive documentation of each of your excipient products and assist you in fulfilling the regulated market requirements. Finding suitable excipients requires knowing the characteristics of the API and excipients to find the ideal formulation. Understanding the role of each excipient and keeping the final goals and objectives in mind, Clyzo helps you select the best ingredients for the suitable formulation.