Determination of Finasteride in Human Plasma and Its Pharmacokinetics and Relative Bioavailability by HPLC-Electrospray Mass Spectrometry

Topical finasteride results in plasma levels 100 times lower than oral finasteride, potentially reducing systemic side effects. Users report similar efficacy with fewer side effects, suggesting a preference for topical application.

The user is on Finasteride for hair loss, taking 0.5mg daily, and plans to reduce the dose to 0.25mg while making lifestyle changes to lower prolactin, SHGB, and cortisol. They will retest in 90 days to assess progress and are open to advice.

Maximum serum DHT suppression for finasteride occurs at 8 hours, while for dutasteride, it occurs within 1 to 2 weeks with daily dosing. Dutasteride mesotherapy will be followed by blood tests to check serum DHT changes.

A peptide-based delivery system for finasteride shows promise in reducing systemic side effects while maintaining hair growth effectiveness. Combining this with other treatments like minoxidil and RU58841 could enhance results with lower systemic absorption.

The user experienced a significant drop in libido and erectile issues after increasing their finasteride dosage, combining oral and topical treatments. They plan to take a break and resume using a lower concentration of topical finasteride to manage side effects.

Topical finasteride may have higher systemic absorption and lower efficacy when using a Propylene Glycol/Ethanol formulation compared to the hydroxypropyl chitosan (HPCH) formulation. The safety profile of topical finasteride relies heavily on the HPCH formulation, and using standard solutions might lead to different pharmacokinetics.