Sumatriptan, a serotonin agonist, is an anti migraine preparation. It may be given orally (100 mg) or subcutaneously (6 mg). Why are the concentrations so different with the two different routes of administration?
a. oral administration is subject to a high hepatic first pass
b. most of the drug given orally is destroyed in the acid environment of the duodenum
c. higher subcutaneous doses result in potent local vasodilation and oedema
d. the oral form is a solid, the subcutaneous form is a liquid.
a. oral administration is subject to a high hepatic first pass??