This document discusses prodrugs, which are medications that are metabolized in the body into an active drug. Prodrugs can improve how drugs are absorbed, distributed, metabolized, and excreted. Prodrugs are classified based on their structure and include carrier-linked bipartite, tripartite, and mutual prodrugs as well as bioprecursor prodrugs. The objectives of prodrugs are to improve solubility, stability, bioavailability, and therapeutic effects while decreasing toxicity. Examples are given of prodrugs that increase stability, such as levodopa, and those that increase bioavailability, such as ampicillin esters.

1. Concept of Prodrug
Submitted By:
Saurabh sharma1

2. CONTENTS
 Introduuction
 Objective Prodrug
 Classification of Prodrug
 Prodrug increasing chemical stbility
 Prodrug increasing Bioavailability
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3. INTRODUCTION
•A prodrug is a medication or compound that,
after administration, is metabolized (i.e., converted
within the body) into a pharmacologically active drug.
•Instead of administering a drug directly, a
corresponding prodrug might be used to improve how
a medicine is absorbed, distributed, metabolized and
excreted.
•For example,Sulfasalazine is a prodrug. It is not active
in its ingested form. It has to be broken down by
bacteria in the colon into two products i.e. 5-
aminosalicylic acid (5ASA) and sulfapyridine - before
becoming active as a drug. 3

4. Drug
Pro
moiet
y
Drug Pro
Drug
Pro
moiet
y
Drug
Schematic illusteration of the prodtrug
concept-4

5. Objective of Pro Drug
1. Pharmaceutical Objectives:
 To improve solubility, chemical stability, and
organoleptic properties
 To decrease irritation and/or pain after local
administration,
 To reduce problems related with the
pharmaceutical technology of the active agent.
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6.  2. Pharmacokinetic Objectives:
 To improve absorption (oral and by non-oral
routes).
 To decrease presystemic metabolism to
improve time profile.
 To increase organ/ tissue-selective delivery of
the active agent.
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7. 3. Pharmacodynamic Objectives:
 To decrease toxicity and improve therapeutic
index.
 To design single chemical entities combining
two drugs (co-drugs strategy).
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8. Classification of Prodrugs
 Prodrug based on structural association of
molecules
• Carrier linked prodrugs
-Bipartite Prodrug
-Tripartite Prodrug
-Mutual Prodrug
• Bio precursor - Esters - Prodrug for amide, imides
and acidic compounds
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9. Carrier linked drug
Carrier linked prodrug consists of the attachment of
a carrier group to the active drug to alter its
physicochemical properties.
They are classified into three group
 Bipartite prodrug E.g. Tolmetin-glycine prodrug.
 Tripartite prodrug Eg becampicillin
 Mutual Prodrugs Eg Benorylate is a mutual prodrug
aspirin and paracetamol.
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10. Bioprecursor Prodrug
 The bioprecursor does not contain a temporary linkage
between the active drug and carrier moiety, but designed
from a molecular modification of an active principle itself.
 Eg: phenylbutazone. Phenylbutazone gets metabolized to
oxyphenbutazone that is responsible for the anti inflammatory
activity of the parent drug
phenybutazone oxyphenbutazone
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11. Prodrug in increasing chemical
stability
 Chemical stability is an utmost necessary
parameter for every therapeutic agent.
 The prodrug approach is based on the
modification of the functional group
responsible for the instability or by changing
the physical properties of the drug resulting in
the reduction of contact between the drug and
the media in which it is unstable.
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12.  E.g levodopa prodrug is taken instead to
dopamine because dopamine cannot cross blood
brain barrier but levodapa can easily cross BBB
and then converted to dopamine.
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13.  E.g Hetacillin taken as prodrug of Ampicillin
because auto aminolysis occur in ampicillina
prodrug of ampicillin formed by the reaction of
acetone and ampicillin „ties up‟ the amine
group and thus inhibits auto aminolysis
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14. Prodrug increasing
Bioavailability
 Prodrug design has been utilized in a number
of cases to optimize the absorption of such
drugs therebyimproving their bioavailability.
Example: Ampicillin is used as their lipophilic
esters like pivampicillin & bacampicillin to
improve drug bioavailability.
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15. Ampicillin
Becampicillin
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16. reference
 https://www.slideshare.net/JanetThomas10/pr
odrugs-concept-applications
 http://www.rroij.com/open-access/prodrug-
design-and-its-applications.php?aid=53092
 https://www.slideshare.net/JanetThomas10/pr
odrugs-concept-
applications?from_action=save
 https://www.chemicool.com/definition/bioprecu
rsor_prodrug.html
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