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Associate Professor D E Moore |
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Loss of potency - lessens therapeutic effect |
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Drug degrades to a toxic substance |
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Degradation leads to aesthetically unacceptable
product - change in colour, formation of bad odour and/or taste |
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Stability in GIT important for absorption of
correct form of the drug |
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Hydrolysis |
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Oxidation |
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Isomerization |
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Epimerization |
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Reduction |
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Polymerization |
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Solubility changes |
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Crystal growth |
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Emulsion cracking |
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Protein denaturation |
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Phase separation |
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Packaging failure |
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Sources |
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Environment during formulation and packaging |
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product absorption |
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transmission through package |
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additional internal packaging |
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imperfections in the seal (most important
source) |
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Activated clays / zeolites |
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Silica gel |
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Molecular sieve |
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Calcium oxide |
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Silica gel |
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Silicon dioxide |
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pure, porous, amorphous |
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chemically inert, non-toxic, resists attrition |
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high capacity > 40% RH |
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low capacity < 40% RH |
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fair capacity > 32oC |
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impregnation with CoCl2: colour
change |
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most common |
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Activated clay |
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Mined and processed |
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variation in properties |
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Oxide of silicon, aluminium, iron and magnesium |
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fair absorption capacity at low RH |
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poor capacity >32oC |
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inexpensive |
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specific applications |
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Activated carbon |
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adsorbs organic compounds |
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can be combined with desiccants or oxygen
absorbers |
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non-toxic |
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can be formulated with pharmaceuticals |
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Ferrous based materials |
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absorb oxygen |
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irreversible reaction |
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release of components of container into contents |
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increased by |
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increased temperature |
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agitation |
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polymer additives |
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ability to protect |
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well closed |
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tight |
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hermetic |
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airtight |
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sealed |
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headspace |
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number of doses |
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single dose |
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multidose |
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tamper evident |
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child resistant |
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Mechanical hazards |
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shock or impact |
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compression |
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vibration |
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abrasion |
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puncture |
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Biological hazards |
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microbes |
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vermin |
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humans |
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Environmental hazards |
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moisture |
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temperature |
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pressure |
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light |
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gases |
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Chemical hazards |
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adsorption |
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absorption and loss |
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leaching |
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detachment of container |
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Commentaires
