Administration, OralBiological AvailabilityArea Under CurveDose-Response Relationship, DrugDrug Administration ScheduleDelayed-Action PreparationsHalf-LifeDrug InteractionsChromatography, High Pressure LiquidDouble-Blind MethodTime FactorsTreatment OutcomeInjections, IntravenousRats, Sprague-DawleyUnited States Food and Drug AdministrationDrug Administration RoutesRats, WistarInjections, IntraperitonealDisease Models, AnimalInjections, SubcutaneousInfusions, IntravenousAdministration, IntranasalLiverLethal Dose 50Injections, IntramuscularRadiation DosageAdministration, RectalAdministration, TopicalMice, Inbred C57BLMice, Inbred BALB CRats, Inbred StrainsInjections, IntraventricularDogsAdministration, IntravenousAdministration, InhalationBlood PressureMetabolic Clearance RateBody WeightAdministration, CutaneousKidneyRandom AllocationRadiometryInfusions, ParenteralBrainAntineoplastic AgentsDrug ToleranceDrug Therapy, CombinationRecombinant ProteinsBehavior, AnimalAnalysis of VarianceMorphinePlant ExtractsDrug CombinationsAdministration, SublingualTissue DistributionRabbitsInjectionsAnalgesics, OpioidRats, Inbred F344LungHeart RateMice, Inbred ICRInjections, SpinalPregnancyCross-Over StudiesDose-Response Relationship, RadiationAntibodies, MonoclonalNeoplasmsEthanolRNA, MessengerDrug SynergismMice, Inbred StrainsMotor ActivityHemodynamicsDrug Evaluation, PreclinicalSelf AdministrationRadiotherapy DosagePiperidinesEstradiolAnalgesicsDose FractionationAnti-Inflammatory Agents, Non-SteroidalEnzyme InhibitorsProdrugsSpleenIntestinal AbsorptionProspective StudiesDrug EvaluationCells, CulturedMice, KnockoutAnti-Bacterial AgentsCocaineBlood GlucoseOrgan SizeAnti-Inflammatory AgentsIodine RadioisotopesBiotransformationNaloxoneKineticsAbsorption