1t·,1·
·/~ L
1:'. .....
'$-
f'-'
·~
DOSAGE FORMS
'.
' (CLASSIFICATION AND DEFINITIONS)
LEARNING OBJECTIVES
On completion of this chapter students will come to know about the following aspects:
• Importance of dosage form.
• The basics of dosage form and its types.
• Definitions of various tvt>es of dosaee form.
2.1 INTRODUCTION
i
,, .r
• DRUG: A drug may be defined as a chemical or biological agent intended for diagnosis,
· mitigation, treatment, cure or prevention of ·disease in human or animals. These' may
exist in solid, liquid, semisolid or gaseous state and administered internally, applied
topically, inhaled or injected.
• SOURCES OF DRUGS: Natural sources include plants, animals and minerals. Among
the natural sources, plants were mainly used: Sometimes minerals and occasionally
animals were used for the same purpose. Today majority of drugs are synthetic and are
manufactured in the laboratory and large number of drugs are obtained from micro-
organisms. .,H
1) Natural sources
The sources of drugs are classified as:
a) Plant: ex. Steroids from Dioscorea species, .vinca alkaloids
. etc.
b) Gland secretions (Animal): ex. Insulin,.thyroid extract etc.
c) Micro-organisms: Penicillin, streptomycin etc.
d) Marine: Anti-neoplastic agents Ara-c (Cytarabine) etc.
e) Mineral: Kaolin, liquid paraffin etc.
2) Synthetic drugs: ex. Aspirin, ibuprofen etc.
3) Semi-synthetic drugs: ex. Antibiotics etc. ._; ;.,. 1
4) Biotechnology: Large number of New Biological Entities (NBEs) are developed using
genetic engineering, broadly called as Genomics and Proteomics.Ex. Hematopoietic stem
cells, tissue specific stem cells etc
@
, ,l Dosage Forms (Classiffcation and Definitions) 23
1 2.2 DOSAGE FORMS
~~!; The drug also called as active ingredient is the biochemically reactive component of the
pharmaceutical product. An active ingredient is rarely given in pure form. When a drug
!,
component (API) is mixed with a suitable non-drug inert component (additives) and
·_t
produced in a definite physical form of definite size and shape suitable for
administration by a particular route of administration, it is called as dosage form.
Following . are the various reasons for conversion of a drug into its various dosage
forms
1. Dosage forms are convenient to pack and handle than 'the corresponding APL
2. To improve palatability. E.g. colored, ~weeten~d and flavoured preparations.
1
3. To protect 'the drugs from 'the pre-systemic degradations. E.g. insulin injections,
sublingual tablets of nitroglycerine.
4. To protect 'the drug substances from oxidation, reduction and hydrolysis. E.g. coated
;,
,sis, cI,-,:C 1: • " '
tablets.
-~ •; ··~·: 5~.._To provide liquid preparations of the drugs w~ch are insoh,1ble in ·differen~ vehicles.
1ay
ied L .<: _
~, -.- E.g. suspension.
6. To provide liquid dosage form of the drugs soluble in a suitable vehicle. E.g.
ng ;:. '! ,,r,, .'~. solutions.
uy· 1 :ru . . 7. ~• To provide the drugs within body tiss1:1es. E. g. injections.
re .;, '.• "' ·8. - to facilitate the administration of drug substances t~ have better patient compliance
o- -u; '9; ' To enhance stability of drug at normal storage conditions. ·
10. To ease transportation, distribution, production and effectiveness of therapy. ·
-r-1-r" 11. To provide a safe and convenient delivery of accurate dosage.
12. To provide for the optimum drug action through inhalation.
13. To deliver drugs into body cavities. E.g. rectal suppositories.
14. To provide for the maximum drug action from topical administration sites. E.g.
sustained release tablets.
15. To avoid local irritations or injury when they are present at high concentrations at
the site of administration. ·
16. To modify pka profile of drug to enhance bioavailability.
·/~ L
1:'. .....
'$-
f'-'
·~
DOSAGE FORMS
'.
' (CLASSIFICATION AND DEFINITIONS)
LEARNING OBJECTIVES
On completion of this chapter students will come to know about the following aspects:
• Importance of dosage form.
• The basics of dosage form and its types.
• Definitions of various tvt>es of dosaee form.
2.1 INTRODUCTION
i
,, .r
• DRUG: A drug may be defined as a chemical or biological agent intended for diagnosis,
· mitigation, treatment, cure or prevention of ·disease in human or animals. These' may
exist in solid, liquid, semisolid or gaseous state and administered internally, applied
topically, inhaled or injected.
• SOURCES OF DRUGS: Natural sources include plants, animals and minerals. Among
the natural sources, plants were mainly used: Sometimes minerals and occasionally
animals were used for the same purpose. Today majority of drugs are synthetic and are
manufactured in the laboratory and large number of drugs are obtained from micro-
organisms. .,H
1) Natural sources
The sources of drugs are classified as:
a) Plant: ex. Steroids from Dioscorea species, .vinca alkaloids
. etc.
b) Gland secretions (Animal): ex. Insulin,.thyroid extract etc.
c) Micro-organisms: Penicillin, streptomycin etc.
d) Marine: Anti-neoplastic agents Ara-c (Cytarabine) etc.
e) Mineral: Kaolin, liquid paraffin etc.
2) Synthetic drugs: ex. Aspirin, ibuprofen etc.
3) Semi-synthetic drugs: ex. Antibiotics etc. ._; ;.,. 1
4) Biotechnology: Large number of New Biological Entities (NBEs) are developed using
genetic engineering, broadly called as Genomics and Proteomics.Ex. Hematopoietic stem
cells, tissue specific stem cells etc
@
, ,l Dosage Forms (Classiffcation and Definitions) 23
1 2.2 DOSAGE FORMS
~~!; The drug also called as active ingredient is the biochemically reactive component of the
pharmaceutical product. An active ingredient is rarely given in pure form. When a drug
!,
component (API) is mixed with a suitable non-drug inert component (additives) and
·_t
produced in a definite physical form of definite size and shape suitable for
administration by a particular route of administration, it is called as dosage form.
Following . are the various reasons for conversion of a drug into its various dosage
forms
1. Dosage forms are convenient to pack and handle than 'the corresponding APL
2. To improve palatability. E.g. colored, ~weeten~d and flavoured preparations.
1
3. To protect 'the drugs from 'the pre-systemic degradations. E.g. insulin injections,
sublingual tablets of nitroglycerine.
4. To protect 'the drug substances from oxidation, reduction and hydrolysis. E.g. coated
;,
,sis, cI,-,:C 1: • " '
tablets.
-~ •; ··~·: 5~.._To provide liquid preparations of the drugs w~ch are insoh,1ble in ·differen~ vehicles.
1ay
ied L .<: _
~, -.- E.g. suspension.
6. To provide liquid dosage form of the drugs soluble in a suitable vehicle. E.g.
ng ;:. '! ,,r,, .'~. solutions.
uy· 1 :ru . . 7. ~• To provide the drugs within body tiss1:1es. E. g. injections.
re .;, '.• "' ·8. - to facilitate the administration of drug substances t~ have better patient compliance
o- -u; '9; ' To enhance stability of drug at normal storage conditions. ·
10. To ease transportation, distribution, production and effectiveness of therapy. ·
-r-1-r" 11. To provide a safe and convenient delivery of accurate dosage.
12. To provide for the optimum drug action through inhalation.
13. To deliver drugs into body cavities. E.g. rectal suppositories.
14. To provide for the maximum drug action from topical administration sites. E.g.
sustained release tablets.
15. To avoid local irritations or injury when they are present at high concentrations at
the site of administration. ·
16. To modify pka profile of drug to enhance bioavailability.
