The major barrier to transdermal drug transport is percutaneous absorption. True False

The ideal molecular weight of a drug intended for percutaneous absorption is above 500. True False

AbsorptionDrug moves from site of administration into the blood, crossing at least one membrane (except if administered IV)To cross membranes, drugs must be in solution and lipid solubleInfluenced by..oRoute of administrationoDosage form – solution, tablet, suppository, etc.oSolubility of the drug – if lipid soluble, drugs cross membranes more easilyoOther factors – food in stomach, type of food in stomach; movement of drug through stomach and small intestine, pH of stomach/intestinal fluids, etc.First-pass effect – influences bioavailability of the drugBioavailability of the drug - “portion of a [drug] dose that reaches systemic circulation and is available to act on body cells

Absorption of vitamin E is through _____.Multiple choice question.passive diffusionactive transport

Select a true statement about active transportIt takes place in both directionsIt occurs without the help of carrier proteinsIt allows all transmissible molecules to pass through membraneNone of the above

True or false? Active transport can only take place across a membrane.