OPIOID PEPTIDE ANALOGS - RECONSIDERATION AS A POTENTIALLY NEW-GENERATION OF ANALGESICS

The use of opioid drugs is often accompanied by centrally mediated sid e effects, such as dependence, tolerance, or respiratory depression.,A dditionally, all commercial opioid drugs have abuse potential. Analogu es of opioid peptides with no or low blood-brain barrier permeability seem to have disadvantages because of their low likelihood of effectiv eness after systemic (eg. oral or intravenous) administration. Neverth eless, such compounds offer minimal systemic side effects if delivered centrally and minimal drug abuse potential. Optimal-effectiveness of opioid peptides requires targeted techniques of delivery which are mor e and more common in modem pain treatment. Peripheral opioid peptide d elivery to augment effects of classical drugs with mainly central acti ons is an additional possible therapeutic application of opioid peptid e analogues with low blood-brain barrier permeability. Therefore, we b elieve that opioid peptide analogues have to be considered as a new ge neration of analgesics.