Types of Capsule Shells Used in Manufacturing

Capsules are popular pharmaceutical dosage forms used to encapsulate and deliver medications. There are two main
types of capsule shells used in manufacturing, each with its unique properties and applications.

1. Hard Gelatin Capsules

Hard gelatin capsules (HGC) are the most commonly used type of capsules in the pharmaceutical industry. They are
made from two-piece, cylindrical shells composed of gelatin and water. The gelatin used is typically derived from
animal collagen, making these capsules unsuitable for vegetarians and individuals with dietary restrictions. Hard
gelatin capsules are available in various sizes, allowing for flexibility in formulating different drug doses. Key
characteristics of hard gelatin capsules include:

• Compatibility: Hard gelatin capsules are compatible with a wide range of drugs, both solid and
  liquid formulations.
• Manufacturing: The manufacturing process of hard gelatin capsules involves simpler and
  cost-effective techniques.
• Disintegration: Hard gelatin capsules disintegrate rapidly in the gastrointestinal tract,
  allowing for efficient drug release and absorption.
• Protection: They offer protection for the drug, preventing direct exposure to external factors
  and degradation.
• Appearance: Hard gelatin capsules have a transparent, glossy appearance.
• Brand Identification: Manufacturers can print logos, product information, and branding on the
  capsules’ outer surface to enhance product identification and brand recognition.

2. Soft Gelatin Capsules

Soft gelatin capsules (SGC) are another widely used type of capsules, particularly for liquid or semi-solid
formulations. Unlike hard gelatin capsules, soft gelatin capsules have a one-piece, hermetically sealed shell
composed of gelatin, plasticizers, and water. The gelatin used in soft gelatin capsules can be sourced from animal
or plant origins, making them suitable for vegetarians. Key characteristics of soft gelatin capsules include:

• Compatibility: Soft gelatin capsules are ideal for liquid or lipid-based formulations, making
  them suitable for poorly water-soluble drugs.
• Manufacturing: The manufacturing process for soft gelatin capsules requires specialized and
  more complex equipment.
• Drug Release: Soft gelatin capsules provide better control over drug release rates, facilitating
  extended or delayed release formulations.
• Protection: They offer protection for sensitive ingredients, such as oils, enzymes, and
  probiotics.
• Appearance: Soft gelatin capsules can be opaque or transparent and may be available in various
  colors, enhancing brand recognition and patient acceptability.
• Swallowability: The smooth, gel-like shell of soft gelatin capsules makes them easier to
  swallow for some patients compared to larger hard gelatin capsules or tablets.

Conclusion

Hard gelatin capsules and soft gelatin capsules are the two main types of capsule shells used in pharmaceutical
manufacturing. Each type offers distinct advantages and is suitable for specific drug formulations. Pharmaceutical
manufacturers carefully select the appropriate capsule type based on the drug’s properties, dosing requirements,
patient acceptability, and other formulation considerations to ensure safe and effective medication delivery to
patients.