QIf topical minoxidil produced less than ideal benefit, even after 6 months of continuous use, is it worth trying oral minoxidil?

Cynthia Trickett, PA-C, MPAS

Cynthia Trickett, PA-C, MPAS

Medically reviewed on 9.1.2023 by Gary Goldenberg, MD

Yes.  Here are a few reasons why I would suggest oral minoxidil instead of topical.

  1. Using topical minoxidil can cause unacceptable hair texture change (greasy, sticky, or ‘crunchy’).
  2. Topical minoxidil use may cause irritation or allergy.
  3. Topical minoxidil demonstrates less than 10% improvement of hair follicle miniaturization.

The enzyme necessary to convert minoxidil to the active form is sulfotranferase.  Some individuals do not have enough of this enzyme present in the hair follicle; therefore, the active form isn’t available in sufficient quantity to act when applied topically.  This enzyme is present in the liver and can convert an oral drug to an active drug for follicular effect.1

It is theorized that minoxidil may increase blood flow to the hair follicle by widening scalp blood vessels, thus increasing nutrients and oxygen to the scalp hair follicular unit.  It is also thought to lengthen the hair growth cycle (anagen phase), shorten the telogen phase, and thicken hair shaft diameter.2


  1. Badri T, Nessel TA, Kumar D D. Minoxidil. [Updated 2023 Feb 21]. In:   StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482378/
  2. Messenger AG, Rundegren J. Minoxidil: mechanisms of action on hair growth. Br J Dermatol. 2004 Feb;150(2):186-94. doi: 10.1111/j.1365-2133.2004.05785.x. PMID: 14996087.