Types and sizes of capsules
Hard gelatin capsules: Hard capsules are made up of base consisting of plasticizers and water. It may also contain colours, sugars, flavours, dyes and preservatives. Gelatin is obtained from animal bones and frozen pork skin. Gelatin obtained from bones and fresh pork skin is mixed and the gel having high strength is used for preparation of hard capsules. Shells are made up of two cylindrical halves; one is large in diameter but shorter in length known as cap and other is shorter in diameter but longer in length called body. The drug is filled in body over which cap is fitted. Hard capsule shells are available in different sizes depending on the quantity of drug to be filled.
| Sizes | Volume (ml) | Locked length (mm) | External diameter (mm) |
| 5 | 0.13 | 11.1 | 4.91 |
| 4 | 0.20 | 14.8 | 5.31 |
| 3 | 0.27 | 15.9 | 5.82 |
| 2 | 0.37 | 18 | 6.35 |
| 1 | 0.48 | 19.4 | 6.91 |
| 0 | 0.67 | 21.7 | 7.65 |
| 0E | 0.7 | 23.1 | 7.65 |
| 00 | 0.95 | 23.3 | 8.53 |
| 000 | 1.36 | 26.14 | 9.91 |
| 13 | 3.2 | 30 | 15.3 |
| 12 | 5 | 40.5 | 15.3 |
| 12el | 7.5 | 57 | 15.5 |
| 11 | 10 | 47.5 | 20.9 |
| 10 | 18 | 64 | 23.4 |
| 7 | 24 | 78 | 23.4 |
| Su07 | 28 | 88.5 | 23.4 |
Soft gelatin capsules: These capsules are soft, elastic in nature, one piece hermetically sealed. These are prepared from gelatin and water in which glycerin, sorbitol or propylene glycol are added as a plasticizers and gives capsules flexibility. To prevent bacterial and fungal growth, preservatives can be used. These are available in different shapes and sizes eg, spherical, cylindrical, oval etc. the spherical capsules ar called pearls. the content in soft gelatin capsules varies from 0.1 to 30ml. These are used for filling drugs in liquid form and semisolids. Multivitamins, liver oil, fish oil are dispensed in soft capsules. these are prepared and filled in one continous operation on automatic and semi-automatic machines. ophthalmic ointments are packed in unit dose capsules
