Summary: Retatrutide should not be combined with insulin or sulfonylureas without medical supervision, and caution is advised with anticoagulants, narrow therapeutic index drugs, other GLP-1 receptor agonists, and supplements with hypoglycaemic properties
For those who have seen the headline about a 2022 EU ban on TD, that was on TD as a food additive (a complete separate use from topical sunscreen)
For prescription-compounded topical GHK-Cu, formal cycle breaks are usually not required
"Although birth defects were not observed in rat fetuses exposed to high levels of hydroquinone, we don't have data in humans showing that it is demonstrably safe to use in pregnancy." Thankfully, alternatives exist to keep melasma and post-inflammatory hyperpigmentation at bay
A comparative study on the hydroperoxide and thiol specificity of the glutathione peroxidase family and selenoprotein P