1. GROUP 2
Tablets
- are solid dosage forms usually prepared with the aid of
suitable pharmaceutical excipients
SCOREDORGROOVEDTABLETS
- allows them to be easily broken into two or more parts
- enables the patient to swallow smaller portions as may be desired
or when prescribed
- it allows the tablet to be taken in reduced or divided dosage
2. TYPES OF TABLETS
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COMPRESSED TABLETS
- in addition to the medicinal agent or agents, compressed tablets usually
contain a number of pharmaceutical adjuncts, including the following :
1. Diluents or fillers - which add the necessary bulk to a formulation to
prepare tablets of the desired size.
2. Binders or adhesive - which promote adhesion of the particles of the
formulation,allowing a granulation to be prepared and maintaining the
integrity of the final tablet
3. Disintegrants - which promote breakup of the tablets after administration
to smaller particles for drug availability
4.Antiadherents, glidants, lubricants or lubricating agents - which enhance
the flow of the material into the tablet dies, minimize wear of the punches
and dies, prevent fill material from sticking to the punches and dies, and
produce tablets with a sheen
3. 5. Miscellaneous adjuncts – such as colorants and flavorants
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MULTIPLY COMPRESSED TABLET
- are prepared by subjecting the fill material to more than a single
compression
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SUGARCOATED TABLETS
- compressed tablets may be coated with a colored or an uncolored sugar layer
- the coating is water soluble and quickly dissolves after swallowing
- the sugarcoat protects the enclosed drug from the environment and provides a
barrier to objectinable taste or odor
- Sugarcoating provides both protection and sweet taste but the coating operations
take a long time
4. Disadvantage of sugarcoated tablets: Time and expertise required
in the coating process and the increase in size, weight and
shipping costs
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FILM COATED TABLETS
- These are compressed tablets which are covered with a thin layer or a film of
polymeric substances to protect their contents from moisture or to mask the
taste of the ingredients.
Advantage oversugarcoated : it is more durable, less bulky, and less time
consuming to apply.
5. ●
GELATIN-COATED TABLETS
- recent innovation
- the innovator product, the gelcap, is a capsule shaped compressed tablet that
allows the coated product to be about one-third smaller than a capsule
filled with an equivalent amount of powder
- the gelatin coating facilitates swallowing, and gelatin-coated tablets are more
tamper evident than unsealed capsules
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ENTERIC COATED TABLETS
- have delayed release features
- they are designed to pass unchanged through the stomach to the intestines,
where the tablets disintegrate and allow drug dissolution and absorption and or
effect
- employed when when the drug substance is destroyed by gastric acid or
when bypass of the stomach substantially enhances drug absorption
6. ●
BUCCAL AND SUBLINGUAL TABLETS
- flat, oval tablets intended to be dissolved in the buccal pouch (buccal tablets)
or beneath the tongue (sublingual tablets) for absorption throught the oral
mucosa
- they enable oral absorption of drugs that are destroyed by the gastric juice
and/or are poorly absorbed from the gastrointestinal tract
●Buccal tablets are designed to erode slowly, whereas for those sublingual use
(nitroglycerin) dissolve promptly and provide rapid drug effects.
7. ●
CHEWABLE TABLETS
- which have a smooth, rapid disintegration when chewed or allowed to
dissolve in the mouth, have a creamy base, usually of special flavored and
colored mannitol.
- useful for administration of large tablets to children and adults who have
difficulty swallowing solid dosage forms
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EFFERVESCENT TABLETS
- prepared by compressing granular effervescent salts that release gas when
in contact with water
- these tablets contain medicinal substances that dissolve rapidly when added
to water
8. - the bubble action can assist in breaking up the tablets and enhancing the
dissolution of the active drug
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MOLDED TABLET
- certain tablets, such as tablet triturates, may be prepared by molding rather
than by compression. The resultant tablets are very soft and soluble and are
designed for rapid dissolution.
9. ●
TABLET TRITURATES
-small, usually cylindrical, molded or compressed tablets containing small
amounts of usually potent drugs
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HYPODERMIC TABLETS
- originally used by physicians in extemporaneous preparation of parenteral
solutions
- the required number of tablets was dissolved in a suitable vehicle, sterility,
attained and the injection performed
- tablets were a convenience, since they could be easily carried in the
physician's medicine bag and injections prepared to meet the needs of the
individual patients
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DISPENSING TABLET
- no longer in use
- they might better have been termed compounding tablets because the
pharmacist used them to compound prescriptions; they were not dispensed
as such to the patient
10. ●
IMMEDIATE RELEASE TABLET
- designed to disintegrate and release their medication with no special rate-
controlling features, such as special coatings and other techniques
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INSTANTLY DISINTEGRATING OR DISSOLVING TABLETS
- (rapidly dissolving tablets or RDTs) characterized by disintegrating or
dissolving in a mouth within 1 minute, some 10 seconds
- design for children and the elderly or for any patients who has difficulty in
swallowing tablets
- they liquefy on the tongue and the patient swallow the liquid
11. techniques used to prepare these tablets:
● Lyophilization
● Soft direct compression
- more convenient to carry and administer than oral liquid
●DISADVANTAGES: drug loading, taste masking, friability, manufacturing costs
and
stability of the product
* Lyophilized foam- prepared by foaming a mixture of gelatin, sugar or sugars,
drug and any other components and by pouring the foam into a mold.
➢ Mold- serves as the unit dose dispensing package
Disadvantages:
➢ Taste masking can be a problem, since the drug is incorporated during the
formationvof the tablet itself
➢ Sometimes difficult to remove from the packaging since they are soft and one
should not press on the dosage unit to remove it but should peel off the
material, exposing the tablet in its mold
12. ●
EXTENDED RELEASE TABLET
- sometimes called controlled-release tablet
- designed to release their medication in a predetermined manner over an
extended period
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VAGINAL TABLETS
- also called vaginal inserts
- uncoated, bullet shaped or ovoid tablets inserted into the vagina for local
effects
- they are prepared by compression and shaped to fit snugly on plastic inserter
devices that accompany the product
13. COMPRESSED TABLET
Quality Standards and Compendial Requirements
In addition to the apparent features of tablets, tablets must
meet other quality standards. These include criteria for:
● Weight
● Weight variation
● Content uniformity
● Thickness
● Hardness
● Disintegration
● Dissolution
14. Tablet Weight and USPWeight Variation
- the quantity of fill in the die of a tablet press determines the weight of the
tablet.
- the volume of fill is adjusted with the first few tablets to yield the desired
weight and content
Content Uniformity
- requirements: 85% to 115% of the label claim and the stndard deviation is less
than 6%
Tablet Thickness
- is determined by the diameter of the die, the amount of fill permitted to enter
the die, the compaction characteristics of the fill material, and the force or
pressure applied during compression
Tablet Hardness and friability
* hardness is perhaps the more important criterion since it can affect
disintegration and disolution
* A tablet's durabilty may be determined through the use of a FRIABILATOR–
this apparatus determines the tablet's friability
Friability = the ability of the tablet to resists abrasion, chipping or cracking in
storage, transportation and handling operations.
15. A maximumweight loss of not more than 1% generally is considered
acceptable formost products.
Tablet Disintegration
- for the medicinal agent in a tablet to become fully available for absorption, the
tablet must first disintegrate and discharge the drug to the body fluids for
dissolution.
- important for tablets containing medicinal agents (such as antacids and
antidiarrheals) that are not intended to be absorbed but rather to act locally
within the gastrointestinal tract
16. COMPRESSED TABLET MANUFACTURE
Compressed tablets may be made by three basic methods:
●Wet Granulation
●Dry Granulation
●Direct Compression
WET GRANULATION
Steps required are :
a) Weighing and blending the ingredients
b) Preparing a dampened powder or damp mass
c) Screening the dampened powder or damp mass into pellets or granules
d) Drying the granulation
e) Sizing the granulation by dry screening
f) Adding lubricant and blending
g)Forming tablets by compression
17. Weighing and Blending
- specified quantities of active ingredient, diluent or filler and disintegrating
agent are mixed by mechanical powder blender or mixer until uniform.
FILLERS include: microcrystalline cellulose, starch, powdered sucrose and
calcium phosphate
DISINTEGRATING AGENTS: croscarmellose(2%), corn and potato starches,
sodium starch glycolate(5%), sodium
carboxymethylcellulose,polyvinylpyrollidone (PVP), crospovidone
STARCH is employed, 5 to 10% is usually suitable, but up to 20% may be used
to promote more rapid tablet disintegration
Screening the Damp Mass into Pellets orGranules
- the dampened powder granules are screened or the wet mass is pressed
through a screen (usually 6 to 8 mesh) to prepare the granules
18. QUESTIONS:
1) Type of tablets which allows them to be easily broken into two or
more parts.
2)Promotes break up of tablets after administration to smaller
particles for ready availability.
3)A tablets durability may be determined through the use of
_____________
4-6 )Three basic methods of compressed tablet
7)A process by which solids, liquids, or even gases may be
enclosed in microscopic particles by formation of thin coatings of
wall material around the substance.
8) ______ method is often preferred to slugging
9) Compressed tablet coated with a thin layer of a polymer capable
of forming a skinlike film
10) Also serves as the unit dose dispensing package