How Do You Manufacture Capsules?

In the pharmaceutical industry, capsules are one of the most popular and convenient dosage forms for administering medication. Offering precise dosing, ease of swallowing, and efficient delivery of both solid and liquid formulations, capsules are preferred by both patients and healthcare professionals alike. 

However, behind their seemingly simple appearance lies a complex manufacturing process that ensures quality, safety, and efficacy. Let’s delve into the intricate steps involved in manufacturing capsules.

Step 1: Formulation Development

If you’re considering starting your own capsule line, you should learn the first step in manufacturing it through formulation development. Pharmaceutical scientists meticulously design the composition of the capsule, considering factors such as drug solubility, stability, bioavailability, and patient compliance. 

This stage involves selecting the active pharmaceutical ingredients (APIs), excipients, and any additional components necessary to achieve the desired therapeutic effect.

Step 2: Preparing the Gelatin Solution

Gelatin, derived from collagen, is the primary material for making hard gelatin capsules. In this step, gelatin is mixed with water and other additives, such as plasticizers and colorants, to achieve the desired viscosity, flexibility, and appearance. The solution is heated and stirred until it becomes homogeneous, ensuring uniformity in the capsule shells.

Step 3: Capsule Shell Formation

The gelatin solution is then fed into a capsule-making machine with two rotating drums. These drums consist of thousands of small, cylindrical holes arranged in rows. As the drums rotate, they dip into the gelatin solution, forming a thin film around the holes. The excess gelatin is removed by a scraper, leaving behind evenly coated capsules.

Step 4: Drying the Capsule Shells

After shell formation, the capsules proceed to the drying stage. They are transferred to drying trays or belts and exposed to controlled temperature and humidity conditions. This process removes excess moisture from the gelatin, ensuring the capsules maintain their structural integrity and prevent sticking during subsequent handling.

Step 5: Filling the Capsules

Once the capsule shells have been dried thoroughly, they are poised to receive the exact dosage of the drug formulation. Filling can be done using various techniques, including manual or automated methods. Automatic capsule filling machines precisely dispense the desired amount of powder, granules, or liquid into each capsule, ensuring accuracy and consistency in dosage.

Step 6: Capsule Sealing

After filling, the two halves of the capsules are joined to seal the contents. Various methods can achieve this task, such as mechanical locking, thermal sealing, or adhesive bonding. The sealed capsules undergo inspection to detect any defects, ensuring only high-quality products reach the market.

Step 7: Polishing and Finishing

To enhance the appearance and consumer appeal, capsules may be polished. This involves tumbling the capsules in a rotating drum with polishing agents, such as beeswax or carnauba wax, to give them a glossy finish. Additionally, printing may be applied to the capsules to provide important information such as drug name, strength, and manufacturer details.

Step 8: Quality Control

Strict quality control measures are applied throughout manufacturing to ensure regulatory standards and specifications compliance. This includes testing the raw materials, in-process samples, and finished products for purity, potency, uniformity, and dissolution rate. Any deviations from the predefined criteria are promptly addressed to maintain product quality and safety.

Step 9: Packaging and Distribution

Once the capsules pass quality control tests, they are packaged into blister packs, bottles, or other suitable containers. Proper labeling and packaging ensure accurate identification and safe storage of the medication. The packaged capsules are then distributed to pharmacies, hospitals, and other healthcare facilities for dispensing to patients.

Final Say

The manufacture of capsules is a complex yet meticulously orchestrated process that involves multiple steps to ensure quality, safety, and efficacy. Each phase is essential for providing top-tier medications to patients worldwide, from formulation development to packaging and distribution. By strictly adhering to quality control standards and embrace technological advancements, pharmaceutical manufacturers continue to innovate and refine capsule manufacturing processes, ultimately benefiting patients and healthcare providers.