RESUMO
OBJECTIVE: Our objective was to evaluate the absorption of finasteride administered by oral and topical routes for treatment of androgenetic alopecia, by means of computer simulations using the GastroPlus ® software. MATERIAL AND METHODS: In vivo plasma concentration profile of oral administration of finasteride 1 mg tablets from the literature was used in the software to build a compartmental pharmacokinetic model that was extrapolated to simulate topical administration of finasteride 0.25% solution in the scalp. Results were compared to literature and other drug concentrations (0.1% and 1%) were also predicted. RESULTS: Compared to literature data, predictive plasma curve from oral administration of finasteride 1 mg showed good correlation, R2=0.992, and Cmax=4.6769 ng/mL. Simulations of topical administration in the scalp for finasteride 0.25% solution showed good correlation, R2=0.908, and Cmax=0.04325 ng/mL when compared to literature data. Topical administration was also simulated at concentrations 0.1% and 1%, both with low plasma concentrations. CONCLUSION: The results obtained in this study suggest that topical finasteride is a potential treatment for androgenetic alopecia in the concentrations analyzed using computer simulations in GastroPlus ®.
