Buprenorphine is a potent opiate agonist-antagonist used in the treatm
ent of both acute and chronic pain. Like many opiates, it has low oral
bioavailability due to both presystemic metabolism in the wall of the
gastrointestinal tract and extensive first pass metabolism. Controlle
d delivery of analgesics results in good pain relief and a lower total
requirement for the drug. Buccal delivery offers advantages in terms
of accessibility, avoidance of first pass metabolism and the ability t
o provide controlled delivery for extended periods of time. Buccal per
meation of buprenorphine was measured in vitro and in vivo in the dog
model using prototype non-woven and hydrogel systems. The fluxes of dr
ug were identical from solutions and from non-woven systems in vitro,
providing a reliable way of applying a drug solution to the mucosa wit
hout leaking. A model is described that permits screening of potential
buccal systems in vitro to select a system for in vivo use. In vivo,
steady-state plasma levels were obtained using both non-woven and hydr
ogel systems. Steady state was attained in 1 to 1.5 h and was maintain
ed during the time of application of the system. Assuming that the flu
x in man is similar to that in the dog, controlled buccal delivery of
buprenorphine would provide adequate analgesia over an extended period
of time.