Tableting method

1. TABLETS
PREPARED BY:
ASHWINI JOSHI
ASSISTANT PROFESSOR
SVCP,HYD

2. CONTENTS • INTRODUCTION
• ADVANTAGES & DISADVANTAGES
• TYPES OF TABLETS
• TABLET EXCIPIENTS
• MANUFACTURING PROCESS
• TABLET COATING
• DEFECTS IN TABLETS
• EVALUATION OF TABLETS

3. INTRODUCTION
• Tablets are compressed solid unit dosage form
containing medicament or medicaments usually
circular in shape and may be flat or biconvex.
• Tablet is defined as a compressed solid dosage form
containing medicaments with or without excipients.
• Pharmaceutical tablets are solid, flat or biconvex
dishes, unit dosage form, prepared by compressing a
drugs or a mixture of drugs, with or without diluents.
• It is the most popular dosage form and 70% of the total
medicines are dispensed in the form of Tablet.

4. ADVANTAGES & DISADVANTAGES
• Advantages of tablets:
ü Easy to administered.
ü Easy to dispense.
ü More stable.
ü Accuracy in dose.
ü Bitter and nauseous substance can be easily dispensed.
ü Light and compact.
ü Economical.
ü Sustained release product is possible by enteric coating.
• Disadvantages of tablets:
ü Problem with compression to crystalline drug.
ü Hygroscopic drugs are not suitable for compressed tablets.
ü Drugs with low or poor water solubility, slow dissolution, may be difficult to
formulate.
ü Cost of production may be increase because of coating and encapsulation to
remove bitter and unpleasant taste.
ü Swallowing is difficult especially for children and ill (unconscious) patients.

5. 1. Compressed
tablet, e.g.
Paracetamol tablet
2. Multiple
compressed tablets,
3. Delayed release
tablet, e.g. Enteric
coated Bisacodyl
tablet
4. Sugar coated
tablet, e.g.
Multivitamin tablet
(A) Tablets
ingested orally
1. Buccal tablet, e.g.
Vitamin-c tablet
2. Sublingual tablet,
e.g. Vicks Menthol
tablet
3. Troches or
lozenges
4. Dental cone
(B) Tablets used
in oral cavity
1. Implantation
tablet, e.g.
Testosterone tablet
2. Vaginal tablet,
e.g. Clotrimazole
tablet
(c) Tablets
administeredby
other route
1. Effervescent
tablet, e.g. Disprin
tablet (Aspirin)
2. Dispensing
tablet, e.g. Enzyme
tablet (Digiplex)
3. Hypodermic
tablet
4. Tablet triturates
e.g. Enzyme tablet
(Digiplex)
(D) Tablets used
to prepare
solution:
TYPES OF TABLET

6. TABLETS INGESTED ORALLY
1. Compressed tablet: These are uncoated tablets made by compression of granules. These provides
rapid disintegration and drug release. e.g. Paracetamol tablet.
2. Multiple compressed tablet: These tablets are prepared to separate physically or chemically
incompatible ingredients or to produce repeat action or prolonged action products. The ingredients
of formulation are compressed into a core tablet and the incompatible substance with other
excipients are compressed over the previously compressed core tablet.
3. Sustained action tablet: These tablets when taken orally release the medicament in a sufficient
quantity as and when required to maintain maximum effective concentration of drug in the blood.
4. Enteric coated tablet: These tablets are coated with the material which does not disintegrate in
stomach but passes through as it is i.e. enteric polymer e.g.: Hydroxypropyl methyl cellulose
phthalate etc. These tablets dissolve in intestine and are site specific.
5. Sugar coated tablet: The compressed tablets with sugar coating are called sugar coated tablets. It is
done to mask the bitter and unpleasant taste and odour of the medicament. It enhances the
appearance and protects the drug from atmospheric effects. e.g. Multivitamin tablet
6. Film coated tablet: These are the compressed tablets having a film coating of film coating polymer
like hydroxy propyl cellulose, ethyl cellulose , HPMC. It also protects the formulation from
atmospheric effects. These are tasteless, have increase in tablet weight and have less elegance. e.g.
Metronidazole tablet
7. Chewable tablet: These tablets are chewed in mouth and are broken into small pieces.
Disintegration time is reduced and rate of absorption increases. Easily administered for infants and
elderly persons. e.g. Antacid tablet

7. ORAL CAVITY TABLETS
1. Buccal Tablets:
These tablets are to be placed in buccal pouch or between the gum & lip or cheek. Tablet
dissolve & disintegrated slowly & absorb directly.
2. Sublingual Tablet:
These tablets are to be placed under the longue. They dissolve & disintegrated quickly &
absorbed directly without passing into G.I.T. Buccal and sublingual tablet should be
formulated with bland excipients, which do not stimulate salivation.
3. Lozenge tablet & troches:
These tablets are designed to exert a local effect on mouth or throat. These tablets are
usually used in treatment of sore throat or control coughing. The tablets are usually used to
such drug as anaesthetic, antiseptic and antibacterial agent, demulcent, astringent and
antitussive agent. Lozenges were earlier called pastilles.
4. Dental cones:
These are relatively minor compressed tablet meant for placing them in the empty socket
after tooth extraction. Usually, these tablets contain an antibacterial, compound which is
released slowly. Prevent the growth of bacteria. These tablets may contain an astringent or
coagulant to reduce bleeding. The base for these types is sodium bicarbonate, sodium
chloride or it may be amines acid. These cones generally get dissolved in 20 to 40 min time.

8. TABLETS ADMINISTERED BY OTHER ROUTE
1. Implantation tablet:
These tablets are placed below the skin or inserted subcutaneously by means of a
minor surgical operation and are slowly absorbed. These must be sterile and are
made by heavy compression and fusion. e.g. Testosterone tablet.
2. Vaginal tablet:
These tablets are meant to dissolve slowly in vaginal cavity. These are ovoid or
pear shaped and are used to release steroids, antibacterial and antiseptics etc to
avoid infections. e.g. Clotrimazole tablet.

9. TABLETS USED TO PREPARE SOLUTIONS
1. Effervescent tablet:
These tablets when added in water produce effervescence. So they dissolved
rapidly in water due to the chemical reaction which takes place between alkali
bicarbonate and citric acid or tartaric acid. These tablets are to be protected
from atmospheric moisture during storage (in well closed container). e.g. Disprin
tablet (Aspirin)
2. Dispensing tablet:
These are intended to be added to a given volume of water to produce a solution
of a given concentration. The medicaments given are silver proteinate and
quaternary ammonium compounds. These are highly toxic if taken orally and
great care must be taken in packaging and labelling. e.g. Enzyme tablet (Digiplex)
3. Hypodermic tablet:
These are compressed tablets which are composed of one or more drugs. These
tablets are dissolved in sterile water and administered parenterally.
4. Tablet triturates:
These are small cylindrical, moulded or compressed tablets which contains a
potent medicament with a diluent. On small scale hand operated whereas for
bulk production automated machines are used. e.g. Enzyme tablet (Digiplex)

10. TABLET TYPES AND
EXCIPIENTS
PREPARED BY:
ASHWINI JOSHI
ASSISTANT PROFESSOR
SVCP, HYDERABAD

11. TYPES & CLASSES
OF TABLETS

12. 1.ORALLY INGESTED TABLETS:
Over 90% of tablets
manufactured are
ingested orally.
These are designed
to be swallowed
intact, with
exception of
chewable tablets.

13. COMPRESSED TABLETS OR STANDARD
COMPRESSED TABLETS:
- These are standard uncoated tablets made by compression
using wet granulation, direct compression or double
compression.
-Provide rapid disintegration & drug release.
-Mostly intended to exert local action in GIT.
- Typically include water insoluble drugs such as
antacids and adsorbents.
- Other drugs having systemic effect have some aqueous
solubility, dissolve from tablet and disintntegrate tablet
fragments in GI contents and are then absorbed and
distributed in the body.

14. MULTIPLE COMPRESSED TABLETS:
There are 2 classes of multiple compressed tablets:
1. layered tablets
2. compression coated tablets
-Both types may be either two component or three component
systems: two or three layer tablets, a tablet within a tablet or a tablet
within a tablet within a tablet.
-Both types usually undergo a light compression as each component is
laid down, with the main compression being the final one.

15. -The layered tablet is preferred to the compression coated
tablet because surface contact between layers is lessened
and production is simpler and more rapid.
ADVANTAGES:
-Separate physically or chemically incompatible ingredients.
-Produce prolonged action products.

16. DELAYED ACTION AND ENTERIC COATED TABLETS:
- Delayed action tablets are intended to
release a drug after some delay or after
the tablet has passed through one part of
GI tract into other.
- The enteric coated tablet is the most
common example of a delayed action
type product.
- The polymers used in enteric coating are
acid esters, are insoluble in gastric media
that have a pH of about 4 and begin
dissolving as the tablets enter duodenum
(pH of 4 to 6).
- Cellulose acetate phthalate
- Polyvinylacetate phthalate
- Hydroxypropylmethyl cellulose phthalate

17. Advantages:
Enteric coated tablets are used for drugs such as:
-Drugs irritating to gastric mucosa which include aspirin and strong
electrolytes such as NH4CL.
- Drugs that are destroyed by low pH of stomach
- Drugs that cause nausea and vomiting if released in stomach
-Drugs that are to be released undiluted and in highest possible
concentration within intestine

18. SUGAR-COATED TABLETS:
an elegant, glossy, easy-to-swallow tablet dosage form.
they permit separation of incompatible ingredients
between coating and core, and utilized in preparing
many multivitamin and multivitamin mineral
combinations.
Disadvantages:
The process is time consuming and require skilled
coating artisans.
Sugar coatings typically double tablet weight.
They are easily mistaken for a candy by children.

19. The use of water soluble polymers,
automated-spray coating
equipment, and high-drying-
efficiency sidevented coating pans
have greatly reduced some of
these disadvantages, resulting in:
Ø more elastic and mechanically
stable coatings
Øcoat weight may be 50% or less of
the core weight
Øthe process may be completed in a
day or less.

20. -These are an alternative to sugar coated tablets in which drug is
not required in the coating.
-The film coating composition consists of one or more polymers, a
plasticizer for the polymer and a surfactant, all delivered to the
tablets in solution from an organic or aqueous solvent.
Polymers used: hydroxypropyl cellulose, hydroxypropyl,
methylcellulose, 30% ethylcellulose dispersion (Aquacoat),

21. Advantages:
tasteless.
tablet coating operation takes only one or two hours.
better mechanical strength of the coating based on elasticity
& flexibility of polymer coating.
little increase in tablet weight than sugar-coated
ability to retain debossed markings on the tablet
avoidance of sugar, which is contraindicated in diet of some
people.
Disadvantages:
less attractive and elegant in physical appearance than sugar
coated.

22. CHEWABLE TABLETS:
Intended to be chewed in the mouth prior
to swallowing and are not intended to be
swallowed intact.
Examples:
-Chewable aspirin tablet for children use.
-Antacid tablet
Advantage:
provide a unit dosage form of medication which
can be easily administered to infants and children
or to the elderly, who may have difficulty swallowing a tablet intact.
Disadvantage:
Bitter or foul tasting drugs can not be given by this dosage form

23. 2. TABLETS
USED
IN
THE
ORAL
CAVITY

24. BUCCAL AND SUBLINGUAL TABLETS:
•Small, flat tablets, intended to be held between cheek
and teeth or in the cheek pouch (buccal tablets) or
beneath the tongue (sublingual tablets).
•Release drug contents for absorption directly through
oral mucosa.
•Designed not to disintegrate but to slowly dissolve,
over
a 15 to 30 min
period.
•Produce systemic drug effects as the drug is absorbed
from oral mucosa to blood stream leading directly to
general circulation.
•Shoud be formulated with bland excipients.
Advantages:
•More rapid onset of action.
•It avoids 1st pass metabolism ofdrugs.
•Protects the drug from extensive decomposition of the
gastric
environment.

25. TROCHES AND LOZENGES:
Disc shaped solid dosage forms containing medicinal
agent
& flavoring substance in a hard candy or sugar base.
Intended to exert a local effect in the mouth or
throat.
Commonly used to treat sore throat or to control
coughing in normal cold.
May contain local anesthetics, antiseptics, antibacterials,
demulcents, astringents and antitussives.
Designed not to disintegrate but to dissolve or slowly
erode over a period of 30 min or less in mouth.
Lozenges: also called pastilles or cough drops. They may
be made by compression but are usually formed by
fusion or by a candy-molding machine.
Troches: are made by compression.

26. DENTAL CONES:
-Designed to be placed in the empty
socket remaining following a tooth
extraction.
-It is formulated to dissolve slowly in
presence of a small volume of serum/
fluid over a 20 or
40 min period.
Uses:
-Toprevent multiplication of bacteria
in the socket by employing a slow
releasing antibacterial.
-Toreduce bleeding by containing an
astringent or amino acid.

27. 3. TABLETS ADMINISTERED BY OTHER ROUTES
Vaginal tablets / Inserts:
Uncoated bullet shaped or ovoid tablets.
Designed to undergo slow dissolution
and drug release in vaginal cavity.
It may contain antibacterials, antiseptics or astringents to treat
vaginal infections such as vaginitis or antifungals to treat fungal
infections such as candidiasis or to release steroids for systemic
absorption.
often buffered to promote pH favorable
to action of an antiseptic agent.
Placed in the upper region of vaginal tract by plastic tube inserter.

28. IMPLANTATION/DEPOT TABLETS:
Small, cylindric or rossete shaped forms, not
more than 8mm in length.
Designed for subcutaneous implantation.
Provide as constant a drug delivery rate as
possible.
Provide prolonged drug effects ranging from
one month to a year.
Disadvantages:
It has safety problems
Tissue toxicity problems in the area of
implantation site.

29. 4.TABLETS USED TO PREPARE SOLUTIONS:
Effervescent Tablets:
Designed to produce a solution rapidly with the
simultaneous release of CO2.
prepared by compressing the active ingredients
with mixtures of organic acids such as citric acid or
tartaric acid and NaHCO3.
When such a tablet is dropped into a glass of
water, a chemical reaction is initiated between the
acid and NaHCO3 to form sodium salt of the acid
and to produce CO2 in water. The reaction is quite
rapid and is usually completed within in one
minute or less.
The are packed in hermetic-type foil pouches or
are stack-packed in cylindrical tubes with minimal
air space.
Examples: Aspirin , saline cathartics

30. Advantages:
Provide a mean of extemporaneously
preparing a solution containing accurate
drug dose.
They produce pleasantly flavored
carbonated drink which assists in masking
the taste of certain drugs.
Disadvantages:
Difficulty of producing a chemically stable
product.
Moisture in air during product
preparation may be adequate to initiate
effervescent reactivity.
During the course of reaction, water is
liberated which autocatalyzes the
reaction.
Compression of tablet in the hands of the
consumer.

31. DISPENSING TABLETS:
Intended to be added to a given volume of water
by the pharmacist or the consumer, to produce a
solution of a given drug concentration.
Materials incorporated in dispensing tablets
include mild silver proteinate, bichloride of
mercury and quarternary ammonium compounds.
Disadvantages:
Difficuty with dispensing tablets is that some of
the components previously used in this dosage
form are highly toxic and extremely hazardous and
even lethal if mistakenly swallowed.
Inavailability of sterile water to produce sterile
solutions.

32. HYPODERMIC TABLETS:
They are composed of one or more drugs
with other readily soluble water soluble
ingredients and are intended to be added
to sterile water or WFI.
Advantage:
The physician can carry many vials of
tablets in his bag with only one bottle of
sterile WFI.
Disadvantage:
The likelihood of administering a nonsterile
solution, even though portable sterile
filteration equipment exists to help assure
sterility.

33. TABLET TRITURATES:
Small, usually cylindric molded or compressed tablets.
Provide extemporaneous method of preparation by the pharmacist.
The drugs used were potent and mixed with lactose and a binder such as
powdered acaia, after which the mixture was moistened to produce a
moldable, compactable mass. This mass was forced into holes of a mold
board wood or plastic, after which tablets were ejected using a peg board,
whose pegs matched the holes in the mold, dried and dispensed.
Disadvantages:
Unreliable bioavailability.
Poor content uniformity of tablets containing potent drugs.

34. TABLET EXCIPIENTS

35. • IMPART WEIGHT, ACCURACY, & VOLUME
• IMPROVE SOLUBILITY
• INCREASE STABILITY
• ENHANCE BIOAVAILABILITY
• MODIFY DRUG RELEASE
• ASSIST PRODUCT IDENTIFICATION
• INCREASE PATIENT ACCEPTABILITY
• FACILITATE DOSAGE FORM DESIGN
THESE ARE THE SUBSTANCES ADDED
IN THE MANUFACTURING OF TABLET
AND PERFORM FOLLOWING
FUNCTIONS:

37. 12-07-2016 Sagar Kishor Savale 37
EXCIEPIENTS-
FUNCTIONS
q Impart weight, accuracy, & volume(its allow acccuracy of dose)
q Improve solubility
q Increase stability
q Enhance bioavailability
q Modifying drug release
q Assist pdt identification
q Increase patient acceptability
q Facilitate dosage form design

38. EXCIPIENTFUNCTIONS

39. 1. DILUENTS
Diluents are fillers used to make up required bulk of the
tablet when the drug dosage itself is inadequate to
produce the bulk.
Provide better tablet properties such as improved
cohesion or to promote flow.

40. PROPERTIES OF DILUENTS
1. They must be non toxic
2. They must be commercially available in acceptable grade.
3. Their cost must be low
4. They must be physiologically inert
5. They must be physically & chemically stable by themselves & in
combination with the drugs.
6. They must be free from any unacceptable microbial
contamination.
7. They must not be contraindicated by themselves and in
comibation with the drug and other tablet components.
8. They must be color compatible.
9. They must have no deleterious effect on the bioavailability of
drugs.

41. COMMONLY USED:
1. Lactose-anhydrous and spray dried lactose
2. Directly compressed starch
3. Hydrolyzed starch
4.Microcrystalline cellulose-Avicel
(2 grades: pH 101 and pH 102)
5. Dibasic calcium phosphate dehydrate
6. Calcium sulphate dihydrate
7. Mannitol
8. Sorbitol
9. Sucrose
10. Dextrose

42. 2. BINDERS AND ADHESIVES:
These materials are added either dry or in liquid form to form
granules or to promote cohesive compacts for directly
compressed tablet.
• EXAMPLES:
Natural gums:
Acacia, tragacanth - 10-25% Conc solution
Disadvantages:
variable in composition and performance, based on their natural
origin
heavily contaminated with bacteria
Solution: When these materials are used, wet granulation masses
should be quickly died at 37C to reduce microbial proliferation

43. •Cellulose derivatives: Methyl cellulose, Hydroxy propyl methyl
cellulose, Hydroxy propyl cellulose
Dry: binder properties
Aqueous solutions: adhesive properties.
•Natural protein: Gelatin- 10-20% solution
Advantage: more consistent material & easier to prepare in solution form.
•Glucose:
Advantage:
Disadvantage:
50% soln in water
low cost
bacterial proliferation
•Synthetic polymer: Polyvinylpyrrolidone (PVP)- 2% conc.
• Starch paste: 10-20% soln
• Sodium alginate

44. 3. DISINTEGRANTS
facilitate the breaking or disintegration of tablet when it
contacts water in the GIT.
draw water into the tablet resulting in swelling and cause
the tablet to burst apart.
help in dissolution of the drug and attainment of high
drug bioavailability.
They can increase in volume in the presence of water by
200 to 500%.

45. • Examples:
• Starch- 5-20% of tablet weight.
• Starch derivatives – low substituted carboxymethyl starches (used in
1-8% concentration. 4% usually optimum)
• Pre-gelatinized starches (5%)
• Clays- Veegum HV and bentonite (10%)
• Microcrystalline cellulose
• Cellulose derivatives- Ac- Di-Sol (internally cross linked sodium
carboxymethylcellulose)
• PVP (cross-linked polyvinylpyrrolidone)

46. SUPERDISINTEGRANTS:
Swells up to ten folds within 30 seconds when contact
water.
• Examples:
Crosscarmellose- cross-linked cellulose
Crosspovidone- cross-linked povidone (polymer)
Sodium starch glycolate- cross-linked starch.

47. 4. LUBRICANTS, ANTIADHERENTS AND
GLIDANTS:
Lubricants are intended to reduce the friction during
tablet ejection between the walls of the tablet and the
walls of the die cavity in which the tablet was formed.
Antiadherents are intended to reduce sticking or
adhersion of tablet granulation or powder to the faces
of the punches or to the die walls.
Glidants are intended to promote flow of granules or
powder material by reducing the friction between the
particles.

48. •Antiadherents:
Starch, talc , magnesium stearate
• Glidants:
Corn Starch – 5-10% conc
Talc- 5% conc
Silica derivatives - Colloidal silicas such as Cab-O- Sil in 0.25-3% conc.
Lubricants:
-Stearic acid salts – Calcium and Magnesium stearate
- Stearic acid – it is less effective lubricant than stearic acid salts and also has a lower
melting point.
-Talc – it contains trace quantities of iron, therefore it should be considered carefully.
-PEG-- The finer the particle size of the lubricant, the more effective the lubricant action.

49. 5. COLORING AGENTS:
PURPOSE:
(1) Masking of color drugs
(2) Product Identification
(3) Production of more elegant product
•All coloring agents must be approved and certified by FDA. Two forms
of colors are used in tablet preparation –
FD &C and D & C dyes.
These dyes are applied as solution in the granulating agent or Lake form
of these dyes.
Lakes are dyes absorbed on hydrous oxide and employed as dry
powders for coloring.
• Example:
FD & C blue 2 - Indigo carmine
In any colored tablet, the formulation should be checked for
resistance to color changes on exposure to light.

50. 6. FLAVORING AGENTS:
Used in chewable tablets or tablets
intended to dissolve in mouth.
Flavor oils are used and are added to
tablet granulations in solvents, are
dispersed on clays and other
absorbents or emulsified in aqueous
granulating agent.
The maximum amount of oil that can
be added is 0.5 -0.75%.

51. 7. SWEETENING AGENTS:
Used only in chewable tablets to
exclude or limit the use of sugar in
the tablets.
Examples:
•Saccharine (artificial): 500 times
sweeter than sucrose
Disadvantage: Bitter after taste and
carcinogenic
• Aspartame (artificial):
Disadvantage: Lack of stability in
presence of moisture.
•Mannitol

52. 8. WETTINGAGENTS
• Water molecules attract each other equally in all directions. Water molecules on
the surface, however, can only be pulled into the bulk water by water molecules
underneath, since there are no water molecules to pull in the opposite
direction. The surface tension of water is strong enough to support the weight
of tiny insects such as water striders.
• The surface tension in action can be visualized by placing a small drop of alcohol
on a thin layer of water. Alcohol with lower surface tension mixes with water
causing reduction in the surface tension in the local region. Owing to the higher
surface tension of water in the neighbor, water is pulled from the alcohol
dropped region into the neighbor, and this leads to the formation of a dry spot
in th12e-07m-20i1d6dle of the water layer.

53. API
Filler Mixing of
granulation blend
GranulationBinder(s)
Preparation of
binder solution
Drying
Milling
LOD
Disintegrant
screening
screening Initial Blending
lubricant screening
Final Blending
Compression
Solvent
Film coating agent Preparation
Film Coating of Tablets
Packaging
and Labelling
Weight
Hardness
Friability
FLOW
CHART