Gelatin capsules – uses, types and production

Are gelatin capsules one of the most common forms of administration of drugs and dietary supplements? Although accurate statistics are hard to come by, there is no doubt that it is this form of drugs and dietary supplements that is one of those used most often in their production.
What are the types of gelatin capsules, what is the process of their production, where are they used and what advantages do they have?

Key conclusions

• Gelatin capsules are the optimal dosage form for drugs and dietary supplements – they ensure effective delivery of active ingredients.
• Their quality determines the bioavailability and effectiveness of the components of medicinal products (pharmaceuticals) and food (dietary supplements).
• The availability of different types of capsules gives great flexibility in the selection of the formulation (form) of the preparation and allows very accurate dosage of active ingredients.

What are they and what are their applications?

Gelatin capsules are polymer casings with controlled physical and chemical properties. Manufactured to be filled inside with active substances – they are adapted to different forms of ingredients – powders, granules, suspensions or solutions.
The universal properties of hollow gelatin capsules allow the use of various formulations. The main task of the capsules is to protect the substances from external factors and their optimal release at the target site of the digestive system.

Definition and construction

Gelatin capsules consist of a casing and a filling.
The casing is produced on the basis of animal gelatin (hydrolyzed collagen), glycerol (plasticizer) and water. In addition, it is possible to use dyes and stabilizing substances.
For contract manufacturing of medicines and dietary supplements, empty gelatin capsules without coloring (transparent) or colored (white, red, green, blue, pink and black) are available at Eubioco.
The capsule’s construction ensures a tight seal, and its simple composition eliminates interactions between the casing and the product contents.

Application in the pharmaceutical industry

Gelatin capsules are widely used in drug manufacturing. They work especially well for substances sensitive to moisture, light and oxygen. They protect the contents and ensure their stability.
In pharmacy, empty gelatin capsules are used for:

• manufacturing multicomponent drug products,
• controlled-release drugs,
• preparations containing oils and fat-soluble vitamins,
• administration of active substances with unpleasant taste

Advantages of gelatin capsules

1. Rapid release of active substances in the digestive system.
2. Optimal protection of the contents from the external environment (oxygen, light, moisture).
3. Optimal release depending on the structure of the envelope (immediate or controlled).
4. Flexibility of formulation – possibility to fill the gelatin capsule with various types of substances.
5. Ease of swallowing due to smooth surface.
6. Masking of taste and odor of medicinal substances.
7. Precise dosage of active substances.

Gelatin capsules vs. cellulose capsules vs. tablets

Tablets, gelatin capsules or cellulose capsules – which solution is better? Unfortunately, there is no clear answer to this. To choose the best form of a drug or dietary supplement, it is necessary to pay attention to the specifics of use of the available options.
Gelatin capsules dissolve faster in the digestive system, which naturally translates into faster release of the active substance. Compared to tablets, they have a smoother surface, and do not cause potential difficulties in taking them.
Cellulose (HPMC) capsules are an alternative for those eliminating zoonotic ingredients. Compared to gelatin ones, however, they may exhibit higher moisture permeability.
The chosen form is one of the factors affecting the price of drugs and dietary supplements, but also their bioavailability and thus their effectiveness.

Sizes of gelatin capsules

We use various types of gelatin capsules in the production of drugs and dietary supplements.
For detailed information on the parameters of each, see the table.

Gelatin capsules – sizes
Size	Capacity (ml)	Diameter (mm)	Length (mm)
Gelatin capsules 000	1,37	9,91	26,14
Gelatin capsules 00	0,95	8,53	23,30
Gelatin capsules 0	0,68	7,64	21,70
Gelatin capsules size 1	0,50	6,91	19,40
Gelatin capsules size 2	0,37	6,35	18,00
Gelatin capsules size 3	0,30	5,83	15,90
Gelatin capsules size 4	0,21	5,31	14,30
Gelatin capsules size 5	0,13	4,91	11,10

Types of capsules

Soft

Soft gelatin capsules are one-piece and flexible. They are filled with liquids or suspensions. They are ideal for lipophilic (fat-soluble) substances.

Hard

Hard capsules consist of two parts: the body and the lid. They are used for bulk substances and granules.

Are gelatin capsules harmful?

Gelatin capsules are completely safe. Their production is subject to strict standards.

Summary

Gelatin capsules are a proven solution that has been used for years in the production of drugs and dietary supplements. Their quality, rapid release of active substances and universal applicability are features that are irreplaceable in the market for the production of pharmaceuticals and foodstuffs.
Attention to each element of the product contributes to the highest quality of the final preparation.

FAQ

What is the difference between a capsule and a tablet?

Capsules consist of a casing (usually gelatin), which is filled with the active substance. Tablets are compressed mixtures of active substances and excipients.

What is the purpose of gelatin capsules?

Gelatin capsules mask the unpleasant taste or smell of the drug, protect the active substance from external agents, and allow controlled release of the substance in the body.

Are gelatin capsules healthy?

Gelatin capsules are safe and well tolerated by the body. Gelatin is a natural ingredient of animal origin, virtually free of allergenic properties.

How long does a gelatin capsule dissolve?

The dissolution time of a gelatin capsule depends on its composition and physiological conditions, but usually ranges from a few to several minutes.

Can liquids be poured into gelatin capsules?

Yes, soft gelatin capsules are designed to be filled with liquid active substances.

Can gelatin capsules be chewed?

It is not recommended to bite gelatin capsules, because the casing protects the active substance and ensures its proper release in the body.

Bibliography

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2. Haznar, D., & Garbacz, G. (2009). Wybrane aspekty technologii leków o modyfikowanym uwalnianiu. Farm Pol, 65(10), s. 747-757.
3. Bauer, K.H., Frömming, K.-H, Führer C. (2011). Technologia postaci leku z elementami biofarmacji. Wrocław: MedPharm Polska.
4. Pluta, R., Jankowski, A., & Han, S. (2009). Technologia produkcji kapsułek miękkich. Farm. Przegl. Nauk, 1, 28-31.