dosage-forms-药学英语

1Unit3PharmaceuticsTextADosageforms2Oil-to-waterpartitioncoefficient（油水分配系数）ratioofconcentrationsofacompoundinthetwophasesofamixtureoftwoimmiscible（不混溶的）solventsatequilibrium.water---------------------hydrophilic（亲水的）octanol（辛醇）------hydrophobic（疏水的）Newwordsandexpressions3first-passeffect(首过效应)aphenomenonofdrugmetabolismwherebytheconcentrationofadrugisgreatlyreducedbeforeitreachesthesystemiccirculation.Itisthefractionoflostdrugduringtheprocessofabsorptionwhichisgenerallyrelatedtotheliverandgutwall.4Gutlumen(肠腔)→gutwall（肠道壁）→portalvein（门静脉）→liver（肝脏）→systemiccirculation（体循环）56Dissolution（溶出）Drugliberationfromsolidforms,suchastablets,granules,capsulesetc.drugsinformulationdisintegrateparticlesofsoliddrugreleasedrugsdissolvinginthebodyfluidsabsorbdrugsabsorbedintotheblood7Bioavailability(生物利用度)thefractionofanadministereddoseofunchangeddrugthatreachesthesystemiccirculation,oneoftheprincipalpharmacokineticpropertiesofdrugs.Bioavailabilitymustbeconsideredwhencalculatingdosagesfornon-intravenousroutesofadministration.89IntroductionPharmaceuticsisthedisciplineofpharmacythatdealswithallfacetsoftheprocessofturninganewchemicalentity(NCE)intoamedicationabletobesafelyandeffectivelyusedbypatientsinthecommunity.Pharmaceuticsisthescienceofdosageformdesign.Therearemanychemicalswithknownpharmacologicalpropertiesbutarawchemicalisofnousetoapatient.Pharmaceuticsdealswiththeformulationofapuredrugsubstanceintoadosageform.10SignificanceofdosageformdesigndosageformcanalterthedrugeffectMagnesiumSulfate(硫酸镁)oraladministrationlaxatives（泻药）5%injectionsedative（镇静剂）dosageformcanaltertheonsetofactioninjection/sublingualtabletquicksustainedreleasetabletchronic11dosageformcanalterthetoxicandsideeffectscontrolledreleasepreparationsoftheophylline（茶碱）somedosageformshavetargetingeffecttargeteddrugdeliverysystem(靶向给药系统）dosageformscandirectlyaffectefficacy12dosageform：pharmaceuticaldosageformsaredrugdeliverysystem.isthephysicalformofadoseofachemicalcompoundusedasadrugormedicationintendedforadministrationorconsumption.–Gaseousdosageforms:aerosol(气雾剂)–Liquiddosageforms:solution，emulsion（乳液），syrup，injection，lotion（洗剂），suspension（混悬剂）–Semisoliddosageforms:gels(凝胶剂)，creams（乳膏），ointments（软膏剂），pastes（糊剂）–Soliddosageforms:tablet，capsule，pills(丸剂)，powders（散剂）13solutesolventotherssolutionNon-volatiledrugswatersyrupVolatileorNon-volatiledrugswatersugar/flavoringagentelixirVolatiledrugsWater+ethanolsugarspiritVolatiledrugsWater+ethanolSolutions,syrups,elixirsandspirits14Effervesenttablet（泡腾片）Effervescenttabletsareuncoatedtabletsthatgenerallycontainacidsubstancesandcarbonatesorbicarbonatesandwhichreactrapidlyinthepresenceofwaterbyreleasingcarbondioxide.Theyareintendedtobedissolvedordispersedinwaterbeforeuse.15Buccaltablet(口含片)usuallyasmall,flattabletintendedtobeinsertedinthebuccalpouch（颊囊）,wheretheactiveingredientisabsorbeddirectlythroughtheoralmucosa;suchatabletdissolvesorerodesslowly.16Sublingualtablet（舌下片）Usuallyasmall,flattabletintendedtobeinsertedbeneaththetongue,wheretheactiveingredientisabsorbeddirectlythroughtheoralmucosaandintoblood;suchatabletdissolvesverypromptly.Nitroglycerinsublingualtablet:atypeofvasodilator.Itrelaxesbloodvessels,increasingthebloodandoxygensupplytoyourheart.Thismedicineisusedtorelievechestpaincausedbyangina.17Entericcoatedtablet（肠溶片、肠衣片）Anoraldosageforminwhichatabletiscoatedwithamaterialtopreventorminimizedissolutioninthestomachbutallowdissolutioninthesmallintestine.Thistypeofformulationeitherprotectsthestomachfromapotentiallyirritatingdrug(e.g.,aspirin)orprotectsthedrug(e.g.,erythromycin)frompartialdegradationintheacidicenvironmentofthestomach.18HardcapsuleTheshellofhardgelatincapsulesbasicallyconsistsofgelatin,plasticizers(增塑剂)andwater.Theplasticizersusedareglycerin(甘油),sorbitol（山梨醇）etc19SoftcapsuleThecompositionofsoftgelatincapsuleshellsissimilartothehardgelatincapsulesexceptthatalargerproportionofplasticizerisincorporatedtomakethemsoftandelastic.20Suspension（混悬剂）adispersioncontainingfinelydividedinsolublematerialsuspendedinaliquidmedium.Thesolidparticlesaredispersedthroughoutthemediumthroughmechanicalagitation,withtheuseofcertainsuspendingagents(助悬剂).21Emulsions（乳剂）Emulsionsarebiphasicsystemsconsistingoftwoimmiscibleliquids,oneofwhich(thedispersedphase，分散相)isfinelysubdividedanduniformlydispersedasdropletsthroughouttheotherphase(thecontinuousphase，连续相).Theseimmiscibleliquidsaremademisciblebyaddingathirdsubstanceknownasemulsifyingagent（乳化剂）.Theystabilizethesystembyformingathinfilmaroundtheglobulesofthedispersedphase22O/WW/O23Ointment（软膏剂）Anointmentisahomogeneous,viscous,semi-solidpreparationthatisintendedforexternalapplicationtotheskinormucousmembranes.Ointmentsareusedtopicallyonavarietyofbodysurfaces.Theseincludetheskinandthemucousmembranesoftheeye.24Transdermalpatch(透皮贴剂)Atransdermalpatchisamedicatedadhesivepatchthatisplacedontheskintodeliveraspecificdoseofmedicationthroughtheskinandintothebloodstream25Liner（衬垫）-Protectsthepatchduringstorage.Thelinerisremovedpriortouse.Adhesive（粘胶层）-Servestoadherethec