Determination of Finasteride in Human Plasma by HPLC-MS

A user is seeking feedback on a homemade topical finasteride formula for hair loss, consisting of 7.5 mg of finasteride, propylene glycol, ethanol, and distilled water. They aim to achieve a 0.0125% solution by applying 2 ml daily.

The user reported high testosterone and estradiol levels within range, but unexpectedly high DHT levels after using finasteride and dutasteride for hair loss. Another person suggested the dutasteride might be fake or a bad batch and recommended using the branded Avodart.

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.

The user is concerned about high estradiol and normal DHT levels after 6 months on finasteride and 4 months on weekly dutasteride, noticing hair thinning. They consider increasing dutasteride frequency and adding RU58841 to their regimen.

Switching from finasteride to a generic dutasteride led to unexpectedly high DHT levels, prompting a switch to a reputed brand and consideration of softgel capsules for better absorption. The user plans to retest DHT levels and may return to finasteride if issues persist.

OP asked if a product from Amazon is sufficient to dilute finasteride. A user advised against using propylene glycol alone, suggesting a pre-made solution instead.