In 2023, the American Society of Anesthesiology issued a guidance statement about the use of these medications, also known as GLP-1s (glucagon-like peptide-1)
Approaches such as intrathecal, intracerebroventricular, and intraparenchymal injections, as well as transient BBB disruption, have been employed to deliver drugs with limited CNS bioavailability (Rezaee et al., 2025)
Codeine, which is naturally metabolized to morphine, can similarly be metabolized into morphinone but also into codeinone [38,39]
Readers should interpret findings as hypothesis-generating
Some dermatologists recommend the sandwich method applying moisturizer before and after tretinoin