Capsules are solid dosage forms that enclose medicinal agents or inert substances within a shell made of gelatin. There are two main types of capsules: hard gelatin capsules and soft gelatin capsules. Hard gelatin capsules have two pieces (body and cap) that are manufactured using molds, while soft gelatin capsules are produced using one of two processes - a plate process or rotary die process - that form the capsule as a single unit. The manufacturing of capsules involves precise control of parameters like gelatin viscosity, drying time and temperature to produce uniform capsules of the desired size, shape and quality.

1. Hospital Pharmacy
Manufacturing of Capsule
By: Saroj Poudel To: Mrs.Shibi Thomas
Pharm.D 4th
year Assistant Professor pharmacy
practice

2. CAPSULES ARE SOLID UNIT DOSAGE FORMS IN WHICH
MEDICINAL AGENTS AND /OR INERT SUBSTANCES ARE
ENCLOSED IN A SMALL SHELL OF GELATIN ( HARD OR
SOFT SHELLS)
THE TERM CAPSULE IS DERIVED FROM THE LATIN
WORD’’ CAPSULA’’ MEANING A ‘’SAMLL CONTAINER’’
GELATIN A protein , digested by proteolytic enzymes
is obtained by partial hydrolysis of collagen obtained from
bone, skin, and connective tissue of animals.

3. Manufacture/Production of hard gelatin capsule
shells
Hard gelatin capsules are also known as dry filled
capsules or two piece capsules.
Hard gelatin capsules consists of two parts
known as capsule body (Longer part) and the capsule
cap (shorter part). The drug substance is placed in the
body and the cap is slided over it. Hence enclosing the
drug substance.
MANUFACTURE:
The Manufacturing equipment consist of pins and pegs
made up of stainless steel to produce to produce capsule
shells of desired shapes and sizes. About 50 of these pins
are attached to the plates which are movable. Both caps
and bodies are prepared simultaneously

4. STEPS:
1.Dipping:
Gelatin soln of required viscosity is taken in a
reservoir. The plate holding the pins is lowered into the
reservoir to the suitable depth for the certain period of time.
This helps in achieving proper length and thickness of shells.
2.Drying:
The plate holding the pins is slowly raised from the
gelatin soln and is subjected to blow drying with air having
controlled temperature and humidity. During this period the
gelatin sets or gels over pins.

5. 3. Stripping:
The desired capsule shells are then stripped (removed)
off from the pins by using jaws made up of bronze.
4. Trimming:
The stripped capsules shells are then trimmed
(shortened) by stationary knives to the required length.
5. Joining of capsule caps and bodies:
Finally, the trimmed caps and body parts are joined
and released from the machines.
The width of walls of the capsule shells is to be strictly controlled
for accurate fitting of caps over the bodies. This can be
achieved by controlling the following parameters.

6. a. Viscosity of gelatin solution
b. Time duration of the dipping
c. Speed of spinning of the pins.
The pins used for making bodies of capsules have the
diameter smaller than those used for making caps. This
help in perfect compressing of caps over the bodies.
Hence in the manufacturing of capsule shells, all the
above five steps are carried out one after the other with
extreme care.

7. Manufacturing of Soft gelatin capsules
Production by two processes
1.Plate process
2.Rotary or reciprocating die processes
1.Plate process:
It is a semi autonomic process in which a warm sheet of
soft gelatin is laid over a plate having die pockets.
Vacuum is applied from underside of this plate to pull the
gelatine sheet into the pockets. The liquid medication is
poured into these dies and another sheet of soft gelatin of
similar or a different colour is laid over it. Finally, a die press
which upon application of pressure seals and cuts off the
capsules simultaneously. The capsules are removed and
washed with a volatile solvent. Washing is done to
removed the adhering oil from the capsules.

8. 2. Rotary Die Process:
This process is developed in the year of 1933.
The capsule prepared by this process have uniformly filled
medications with accurate doses.
It is fully automatic continuous process in which the
liquid gelatin is made to flow from an overhead tank to form two gelatin
sheets on two different rotating drums. These gelatin sheets are
conveyed between two rotating dies from opposite direction. As the
sheets comes in between the dies, the metered filling materials is
injected which creates pockets in the sheets. Simultaneously , these
formed pockets are sealed by pressure and heat and are cut off from
the sheets as capsules.
The capsules so formed are adhered with mineral
lubricants applied on gelatin sheets for ease in movement. These
lubricants can be removed by passing the capsules through naphtha
bath. The capsules are then passed through air dryers under pressure to
rinse off the excess moisture. Finally they are proceeded for packaging.

10. ADVANTAGE:
1.Heavy materials like pastes and ointments are easily
encapsulated.
2.Solid medicaments are easily processed with suitable
vehicles and encapsulated.
3.Capsules are filled with accurately measured
medicaments
and tightly sealed.
4.Biocoloured capsules are formed when different
coloured
gelating sheets are used.