This term paper discusses oxidation as a degradation pathway for drugs. It defines degradation as a drug's inability to maintain its initial physical, chemical, therapeutic, and toxicological properties over time. Oxidation is described as a common degradation pathway that can be catalyzed by oxygen, heavy metals, and light, leading to free radical formation. The paper outlines the types of oxidation (auto-oxidation and photo-oxidation), provides examples of drugs that undergo oxidation, and discusses methods to prevent oxidation including the use of antioxidants, chelating agents, and replacing oxygen in drug containers.

1. TERM PAPER
OXIDATION REACTION AS DEGRADATION PATHWAY
CAUSING DECOMPOSITION OF DRUGS
BY
NAZIR MUHAMMAD ADAKAWA
11803340
TO
VANCHA HARISH
DEPARTMENT OF PHARMACEUTICAL SCIENCE
LOVELY PROFESSIONAL UNIVERSITY

2. CONTENTS
Introduction
Definition of terms
Oxidation degradation
Types of oxidation
Drugs undergoing oxidation
Prevention of oxidation
Reference

3. DEGRADATION
„ Is the inability of a particular formulation
in a specific container to remain in its
initial physical, chemical, therapeutic
and toxicological character
STABILITY
„ Is the ability of a drug or formulation to
remain in its fixed character of identity
and purity up to specific period of time

4. OXIDATION DEGRADATION
„ Oxidation is a common pathway for drug degradation in formulations which can be
catalyzed by oxygen, heavy metals and light leading to formation of free radical
„ In pharmaceutical dosage forms oxidation is mediated by reaction with atmospheric
oxygen known as autoxidation
„ Oxidative mechanism involve the elimination of electropositive atom , radical or
electron or addition of electronegative group
„ Alcohols , phenols, amines, sulfides and unsaturated fats and oil are susceptible to
oxidation

5. TYPES OF OXIDATION
Auto-oxidation
„ This oxidation involves or occurs in the
presence of air as O2
„ the reaction proceeds slowly under the
influence of atmospheric oxygen
Photo-oxidation
„ This oxidation electron is removed
without the presence of O2
„ This reaction is less frequently
observed, its mostly occur in
adrenaline and riboflavin
Auto-
oxidation
Photo-
oxidation

6. EXAMPLE OF DRUG UNDERGOING OXIDATION

7. EXAMPLE OF DRUG UNDERGOING
OXIDATION

8. PREVENTION OF OXIDATION
„ Antioxidants ; these agents act by breaking the free the radicals chain
reactions at the step of chain propagation step while other agents
prevents by acting or involving itself in the oxidation rather than the
active drug e.g. . Tocopherols , butylated hydroxyl anisole,
„ Chelating agents ; chelating agents are used when the oxidation is
catalyzed by heavy metals and binds to make complexes e.g. EDTA
„ Replacing oxygen in pharmaceutical container with nitrogen or carbon

9. REFERENCE
Physical pharmaceutics || by Dr. shalini Sharma 2019 edition S vikas publishers
Text book of physical pharmaceutics by C. V. S. Subhrahmanyam