Update: October 2021 — New study finds that low-dose oral minoxidil increases hair density and thickness.

Update: February 2021 — Safety of low-dose oral minoxidil for hair loss in 1404 patients. Multicenter study. The most frequent adverse side effect was hypertrichosis.

Since I first wrote this post on oral Minoxidil several years ago, a number of major new developments have occurred.

An October 2020 study of low-dose 1.25 mg nightly treatment with oral Minoxidil (Loniten) for three months concluded favorable increases in hair growth. More here. This is surprising, considering the low dose utilized relative to other studies. The hair loss patients included males and females of various ethnicities. Further treatment with 2.5 mg dosing was also analyzed.

In September 2020, a Thai study found good results for men taking oral Minox 5mg daily. In July 2020, a review of 16 studies encompassing 622 patients concluded that oral Minoxidil is an effective and well-tolerated hair loss treatment. However, more statistical data is still needed. Also see this June 2020 article that concludes low-dose 1.25 mg/day

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. It was sent to me by Dr. Sergio Vañó.

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.

Body Hair Increase Side Effect

Another major recent news story regarding oral Minoxidil also comes from Spain in August 2019. Apparently, 17 infant children were mistakenly given oral Minoxidil instead of heartburn medication.

Update: December 2020 — Over a year after the medical error, families of some children are complaining that the body hair keeps growing. Also from Spain, a September 2020 study on low-dose oral Minoxidil and hypertrichosis.

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. It is one of only two drugs officially approved by the US FDA to treat male pattern hair loss. The other being Finasteride, which targets dihydrotestosterone (DHT) reduction.

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. Women tend to use the 2% topical formulation to regrow thinning hair. Very few people use oral Minoxidil to treat male androgenetic alopecia or female pattern hair loss.

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.

Low-Dose Oral Minoxidil for Hair Loss

Several years ago, I read a very lengthy and thoughtful comment by Thai hair transplant surgeon Dr. Damkerng Pathomvanich. He outlined 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. Update: In October 2020, Dr. Ratchathorn Panchaprateep from Thailand also released positive findings in relation to this drug.

According to Dr. Path (as well as per 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 Rogaine 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.

Another doctor from Australia recommends oral Minoxidil for hair loss: