General Properties Of Pharmaceutical Capsules

The capsule is a solid dosage form of medication in which one or more active pharmaceutical ingredients (API) and the excipients are enclosed in either a hard or soft soluble gelatin container. They generally contain a single dose of active ingredients and are taken orally. Capsules are faster and simpler to formulate than tablets and other dosage forms and can thus reach the market more quickly.

Pharmaceutical capsules

Capsules may contain medications in solid, paste or liquid forms. The API filled in the capsules may contain excipients as solvents or fillers but the shell should not be attacked by the content thereby releasing the contents of the capsule.

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Excipients such as opaque fillers, antimicrobial preservatives, sweetening agents, permitted flavoring agents and one or more coloring agents may be added. Capsules may be printed on the outer surface.

Properties Of Capsules

Content Characteristics

Soft gel capsules contain liquid or oil-based medications, or medicines mixed or dissolved in oil.” Hard gelatin capsules generally contain dry or powdered substances. The manufacturing process for each type of gel capsule makes each type more suited to its contents. 

Content Composition

Hydrophobic medications are found in softgel. Powdered or solid medications, which are typically found in hard gel caps, tend to be hydrophilic. Additionally, the substance inside a soft gel capsule can be a suspension of large particles floating and not mixing in the oil, or a solution in which the ingredients are completely mixed.

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Digestibility

Gelatin is a protein made from animal skin or bones. These proteins lend easy digestibility to the capsules. In certain cases, medication enclosed in gelatin capsules enters the system quicker than with other medication types. Vegan gelatin capsules are made from cellulose, a plant fiber, which is harder for the body to digest than animal fiber.

Airtight Seal

Gelatin capsules are airtight. This is particularly useful for liquid medications. If the same liquid medications were sold in an unencapsulated form, the contents might go bad before the consumer could use the entire contents of the bottle. The airtight seal created during the manufacture of gel caps prevents potentially harmful microorganisms from forming in the medication. Gelatin capsules offer single-serve doses of medications with a longer shelf life compared to their liquid counterparts.