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level: Level 2

Questions and Answers List

level questions: Level 2

Question	Answer
It is usually a RESULT of CHEMICAL INTERACTION taking place AMONG THE INGREDIENTS of a prescription. Such interactions may TAKE PLACE IMMEDIATELY UPON COMPOUNDING when these are termed as immediate incompatibilities and are evident as effervescence, precipitation or colour change.	Chemical Incompatibilities
Such chemical interactions may TAKE PLACE IMMEDIATELY UPON COMPOUNDING these are termed as__ and are evident as effervescence, precipitation or colour change.	Immediate incompatibilities
More often the chemical interaction are NOT EVIDENT IMMEDIATELY on compounding but TAKE PLACE OVER A PERIOD OF TIME. Such interaction are termed __	Delayed incompatibilities
●Loss of electron, reducing agent ●Dehydration ●Increase in oxidation state ●Triggered by oxygen, light, metals ●Manifests as change in color Ex. Ascorbic acid ( white – yellow/ brown), Epinephrine ( clear- pink/violet) Vit. B ( clear- pink)	1.Oxidation
Gain of electrons, oxidizing agents Hydrogenation Decrease in oxidation state Ex. Tollen’s test	2. Reduction
Involving water as solvent MOST COMMON TYPE OF INCOMPATIBILITY MOST COMMON MECHANISM OF DRUG DEGRADATION Susceptible groups: a. lactams ( penicillins and cephalosphorins) B. esters ( cocaine, physostigmine, aspirin, tetracaine, procaine and methyldopa) C. Amides ( dibucaine) D. Imines ( diazepam)	3. Hydrolysis
Interaction of drug with SOLVENT OTHER THAN WATER E. tertiary benzyl chloride	4. Solvolysis
Action or PROCESS OF CHANGING from OPTICALLY ACTIVE compound INTO A RACEMIC COMPOUND or an optically inactive mixture. Racemic mixture: equal amounts of dextro (+) and levo (-) isomers Ex. Thalidomide (s- enantiomer)	5. Racemization
SALTING OUT PROCESS TWO OR MORE DRUGS INTERACTING to FORM a NEW SUBSTANCE Ex. Ca(OH)2 + CO2 → CaCO3 + H2O	6. Precipitation
EFFERVESCENCE E.g effervescent tablet (contains NaHCO3 & tartaric acid & citric acid)	7. Evolution of Gases
Reducing agent (RA) + Oxidizing agent (OA) Ex. Sugar + KMnO4, glycerin + KMnO4, Potassium Chlorate + Sulfur/ Tannic acid	8. Explosive Mixture
Cake formation ( suspensions) Ex. Acacia + Bismuth salts > Cement/ Cake (ABC)	9. Cementation
Gel or gelatin formation Ex. Acacia + Iron salts > Gel ( AFG)	10. Gelatinization
a process of REACTING MONOMER MOLECULES TOGETHER in a chemical reaction to FORM POLYMER CHAINS or THREE-DIMENSIONAL NETWORKS.	11. Polymerization
Degradation by light Manifests as change in color Ex. Nifedipine, nitroprusside, riboflavin, phenothiazines, amphotericin B	12. Photo-oxidation/ Photolysis