The literature indicates that the bioavailability of a drug can vary significantly between different delivery routes, such as intranasal and subcutaneous. For retatrutide, while specific studies comparing these two routes may be limited, intranasal delivery generally offers advantages like bypassing first-pass metabolism and potentially faster onset of action. However, subcutaneous administration is often preferred for its established pharmacokinetics and consistent absorption profiles. Ongoing research will likely provide more insights into the comparative absorption and efficacy of intranasal versus subcutaneous routes for retatrutide.
Source:
Retatrutide: Dose, Results & Where to Buy