<prompt> 100 bioavailiability is seen with which routeOralIntravenousRectalSubcutaneous  <response>: Ans. b IntravenousRef Katzung Pharmacology 10th ed. Ch 3 Bioavailability is defined as the fraction of unchanged drug reaching the systemic circulation following administration by any route.In case a drug is give orally, the bioavailiablity shall be less than 100. This is due to Incomplete extent of absorbtion First pass metabolismRoutes of Administration, Bioavailability, and General CharacteristicsRoute of AdministrationGeneral characteristicsBioavailiabiltyIntravenousOnset of action is fastest100IntramuscularPainful75-100SubcutaneousLesser volumes can be given compared to intramuscular route75-100Per oralMost convenient from patients perspective5 to 100First pass metabolism limits blood levelsPer rectalLess first pass metabolism than peroral30 to 100TransdermalVery slow absorbtion Lack of first pass effect Prolonged duration of action80-100 