DRUG INTERACTIONS: Carbamazepine, rifampin, and St. John's wort may reduce blood levels of finasteride by increasing its breakdown in the liver. Itraconazole, erythromycin and similar drugs increase blood levels of finasteride.
PREGNANCY AND BREASTFEEDING SAFETY: Finasteride should not be used or handled by pregnant females. Finasteride prevents the conversion of testosterone to DHT, a hormone which is necessary for the development of male genitalia. Finasteride should not be used or handled by pregnant mothers due to the potential hazard to the male fetus.
Finasteride should not be used by women. It is not known if finasteride is excreted in human milk.
STORAGE: Tablets should be stored at room temperature, 15 C-30 C (59 F-86 F).
DOSAGE: The recommended dose is one 1 mg tablet (Propecia) once daily. Generally, patients should use 1 mg of finasteride daily for three months or more before any benefits of treatment are observed. If hair loss improvement is not noticed after 12 months, additional finasteride treatments will likely not help.
How does Propecia work?: Finasteride is a synthetic compound that is used for the treatment of male pattern hair loss or androgenetic alopecia in males only. Finasteride blocks conversion of testosterone to dihydrotestosterone (DHT). Finasteride decreases the blood and scalp concentrations of DHT which is thought to be associated with androgenetic alopecia.
Medically reviewed by Eni Williams, PharmD, PhD
REFERENCE: FDA Prescribing Information
Quick GuideHair Loss: Causes, Treatments, and Prevention
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