Administration, OralDrug Administration ScheduleInjections, IntravenousUnited States Food and Drug AdministrationTime FactorsDose-Response Relationship, DrugDrug Administration RoutesRats, Sprague-DawleyRats, WistarAdministration, IntranasalDisease Models, AnimalInjections, IntraperitonealInjections, SubcutaneousMice, Inbred C57BLTreatment OutcomeLiverAdministration, RectalBiological AvailabilityInjections, IntramuscularAdministration, TopicalInfusions, IntravenousHalf-LifeArea Under CurveAdministration, IntravenousDrug InteractionsInjections, IntraventricularMice, Inbred BALB CDouble-Blind MethodTissue DistributionDogsRats, Inbred StrainsAdministration, CutaneousBrainCross-Over StudiesBlood PressureAnalysis of VarianceRandom AllocationKidneyBody WeightAdministration, InhalationAdministration, SublingualBehavior, AnimalInfusions, ParenteralRecombinant ProteinsPregnancyRNA, MessengerInjectionsMorphineDrug TolerancePlant ExtractsRabbitsChromatography, High Pressure LiquidUnited StatesOrgan SizeAntineoplastic AgentsProspective StudiesLungMetabolic Clearance RateInjections, SpinalMotor ActivityMice, Inbred ICRDrug Therapy, CombinationAnalgesics, OpioidDrug CombinationsRats, Inbred F344Heart RateEthanolMice, KnockoutHemodynamicsDrug Evaluation, PreclinicalEstradiolSelf AdministrationAntibodies, MonoclonalReproducibility of ResultsMice, Inbred StrainsAnalgesicsRetrospective StudiesEnzyme InhibitorsImmunohistochemistryBlood GlucoseCells, CulturedSpleenPain MeasurementAnti-Inflammatory Agents, Non-SteroidalPiperidinesInjections, Intra-ArterialProdrugsNeoplasmsPainIntestinal AbsorptionDrug SynergismAdministration, BuccalAnti-Bacterial AgentsDrug ApprovalEatingKineticsCytokinesGenetic TherapyInsulinCocaine