Topical eflornithine (Vaniqa®) in hirsutism

• Eflornithine is a specific, irreversible inhibitor of the enzyme ornithine decarboxylase present in hair follicles
  • ornithine decarboxylase enzyme is responsible for a key step in the biosynthesis of polyamines such as spermidine and putrescine
    • it is believed that these polyamines have important roles in cell proliferation, and blocking them in hair follicles slows the growth of the hair
    • there is a continual regeneration of ornithine decarboxylase. Therefore when inhibition of this enzyme ceases, the functional activity of ornithine decarboxylase increases (i.e. hair growth resumes)
  • topical eflornithine is applied twice daily to affected areas of the face. Adverse effects of eflornithine are generally mild in nature.
    • in the UK topical eflornithine is marketed as a treatment to reduce the frequency of a woman's usual method of hair removal and not as a replacement for the current method

Reference:

Shapiro J. Vaniqa-eflornithine 13.9% cream. Skin Therapy Lett. 2001 Apr;6(7):1-3, 5.