Since I first wrote this post on oral Minoxidil several years ago, a number of major new developments have occurred. In August 2019, Spanish researchers published positive findings on low-dose 5 mg per day oral Minoxidil. One of the results from this study can be seen in the above before and after hair growth photo (sent to me by Dr. Sergio Vañó).

Funnily enough, the other major recent news story regarding oral Minoxidil also comes from Spain (and also from August 2019). How strange a coincidence. Apparently, 17 infant children were mistakenly given oral Minoxidil instead of heartburn medication.

The children subsequently developed a condition called “werewolf syndrome” in which large parts of their bodies become covered in hair. This condition is also referred to as hypertrichosis.

Luckily, the body hair will disappear a few months after the children stop taking oral Minoxidil. Above photo is from the video of this shocking news story.

Introduction

I have discussed Minoxidil (brand name Rogaine) many times on this blog in the past since it is one of only two drugs officially approved by the US FDA to treat hair loss. Most men use 5% topical Minoxidil foam and apply it to their scalps twice per day. For those who get adverse reactions, dosage is sometimes reduced to once per day. Very few people use oral Minoxidil to treat androgenetic alopecia.

Unbeknownst to many, Minoxidil was originally approved in 1979 as an oral medication (brand name “Loniten”) to treat hypertension (high blood pressure). It was only approved for treating hair loss in men in 1988 as a topical medication.

A women’s version was approved in 1991. To this day, it is not entirely clear as to how Minoxidil works in promoting hair growth, with a number of theories out there, implying the likely involvement of multiple mechanisms. These include agonistic affects on adenosine-triphosphate (ATP)-sensitive potassium channels; prostaglandin stimulation in the dermal papillae; and anti-androgenic properties.

Oral Minoxidil for Hair Loss

For many years, I have heard that oral Minoxidil results in even more hair growth compared to the topical version. This is true for both male and female pattern hair loss (often in combination with Spironolactone for women). However, I always assumed that the side effects from the oral medication would be much worse.

The health related side effects include blood pressure fluctuations, heart rate changes, and potential water retention. However, I was most concerned about the side effect of excess body hair growth from Minoxidil pills turning me into a werewolf. Note: Make sure to read my post on topical Minoxidil and beard growth.

Low-Dose Minoxidil for Hair Loss

Several years ago I read a very lengthy and thoughtful comment by respected Thai hair transplant surgeon Dr. Damkerng Pathomvanich about why he prescribes oral Minoxidil to a select few of his patients. Low-dose Minoxidil for hair loss in select patients can be very effective.

According to him as well as other physicians that had given him feedback, 5 mg per day was an ideal dosage that did not change patient blood pressure readings significantly. Some physicians even recommend trying 2.5 mg per day. In fact doses as low as 0.25 mg to 1.25 mg per day have results in hair growth in some patients.

However, some western publications and websites recommend a lower dosage (see links in some of the comments to this post). Image below shows generic 5 mg Minoxidil tablets from Thailand. Please do not try to buy this online as it can be dangerous.

Side effects are still possible at low doses. Dr. Pathomvanich does not prescribe oral Minoxidil to patients who have blood pressure, heart, liver or kidney problems.

Note that according to the official brochure for Loniten, maximum recommended dosage is listed as high as 100 mg per day, which seems crazy. Most patients taking the drug for hypertension do not cross 40 mg per day.

Dr. Sinclair Recommends Oral Minoxidil

I had forgotten about the above till today, when commentator “Billa” posted an interesting link to a new audio interview with Australian Dr. Rodney Sinclair. I have covered this well known hair expert a number of times on this blog in the past.

In this latest interview, one of the things that Dr. Sinclair states is that oral Minoxidil is much more effective than topical Minoxidil when it comes to hair growth. He reaches this conclusion based on some clinical trials that his clinic is currently undertaking.

While the article describing the above interview states that side effects from oral Minoxidil were not significant according to Dr. Sinclair, I did not hear that in the audio interview. I am guessing that this must be true or else they would stop conducting the trials.

Dr Sinclair has also successfully tested oral Minoxidil and Spironolactone combination treatment in female pattern hair loss patients.

Note that oral Minoxidil is not currently FDA approved for treating hair loss. I do not intend to take the drug, mostly because I do not want to risk getting any more body hair.