Androgenetic alopecia or patterned alopecia is a widespread and frustrating form of hair loss that is usually multifactorial. Apart from genetic factors, hormones play a crucial role too. And even though there are FDA-approved options for the treatment of hair loss, they have shown limited success in women, and various side effects further restrict their use.
That’s why off-label treatments like spironolactone have generated dermatologists’ interest as a solution to hair loss woes in women.
What is spironolactone, and how does it work
Spironolactone is traditionally used as a ‘diuretic’ for 60 years, which means to reduce the excess water in the body, like in the case with heart diseases, and reduce the blood pressure. Besides, spironolactone also possesses a significant anti-androgen effect.
Androgens are the male sex hormones that are primarily responsible for making the hair follicles smaller and eventually making them fall out. Spironolactone blocks the androgen production as well as the androgen receptors in the target tissue (e.g.hair follicle).
Since in female pattern hair loss, hair follicles in front ⅔ of the scalp are more sensitive to androgens, spironolactone provides a lucrative therapy option against hair shedding in women.
For around 40 years, this anti-androgen property of spironolactone is exploited in the treatment of acne and oily skin .
Spironolactone formulations and effectiveness for hair loss treatment
Spironolactone is one of the most common systemic therapies used in the US against female pattern hair loss to arrest hair loss and stimulate hair growth .
It is available in the following formulations:
Spironolactone is not FDA-approved for any type of hair loss but has shown pretty impressive success in the pilot studies, and approximately 90 percent of the women using it for over a year reported an arrest of hair loss.
In a study, daily spironolactone oral for 12 months in 40 women showed hair growth in around 44% of the women and control of hair-fall in another 44% of the women. The result was comparable to another conventional anti-androgen medication- cyproterone acetate.
Interestingly, even though it is well established that androgens play an essential role in androgenetic hair loss, none of the women in the study showed raised androgen in the blood, and they still benefited from anti-androgen therapy. That indicates that the results of spironolactone are not dependent on any particular parameter in blood .
In another study, 100 women received minoxidil 0.25 mg and spironolactone 25 mg and were followed prospectively for 12 months. Hair shedding and the balding area’s visual analysis significantly improved in the women who continued the therapy for 12 months. Two women discontinued the treatment due to side effects .
In a single case study with a 53-year-old female with proven female pattern hair loss, as evaluated by scalp photography, spironolactone 200 mg showed hair regrowth at 12 months. The growth, however, plateaued at 24 months.
The authors then added 5% minoxidil twice daily, and further regrowth was observed. In a 4-year follow-up, this hair regrowth was well maintained, suggesting that combination therapy could yield better results than spironolactone alone .
Even in the younger age group, with a familial tendency for androgenetic alopecia, spironolactone has shown efficacy in reducing hair thinning in individual case studies. Spironolactone is especially suitable for females with two or more conditions due to increased sensitivity to androgens like acne, very oily skin, or increased facial hair.
A recent study also concluded that women with higher severity of hair loss respond dramatically in terms of hair growth compared to women with initial androgenetic alopecia who show just a decrease in hair loss and maintenance or a slight improvement in the hair density .
It is known that locally applied spironolactone (5%) can also inhibit the androgen receptors and hence can be, theoretically, used in the treatment of acne .
But topical spironolactone is not much investigated in the treatment of androgenetic alopecia.
A study with 32 patients with 16 receiving spironolactone topically and 16 receiving finasteride topically for six months showed that spironolactone is superior to finasteride in both male and female groups in increasing the hair density .
Topical spironolactone as a mainstream treatment in androgenetic hair loss seems a little wider away on the horizon due to a lack of established efficacy and safety.
Dosages and duration of therapy
The standard dose of Spironolactone is 100-200 mg a day but studies of as little as 25 mg combined with other anti-androgens (like oral minoxidil as mentioned above) have shown positive results. The dose should be raised slowly to control and monitor the side effects.
Initial improvement is seen after a few months, ideally in 6-8 months. The treating physician decides the therapy endpoint, but as long as there are no contraindications, like side effects or pregnancy, the therapy needs to be continued for at least two years. The best results, in multiple studies, have been seen after using spironolactone for 12 months.
Spironolactone vs. finasteride in the treatment of hair loss
There are, unfortunately, no notable head to head studies which compare spironolactone to finasteride, that would let us come up with a reliable conclusion.
The choice to start one particular drug or other depends on many factors like age, desire to get pregnant in the near future, and other co-existing health or skin-related concerns.
Spironolactone in male pattern hair loss
Even though it is effective , spironolactone is seldom used in the treatment of male pattern hair loss due to chances of feminizing effect like breast enlargement, as well as due to other much more effective and FDA-approved options available like finasteride or dutasteride.
Spironolactone can also cause loss of libido and sexual dysfunction in males, with high doses of 400 mg a day, even causing a decrease in fertility and sperm count.
Side effects of spironolactone in women
Although not very pleasant to look at, the side effect profile of spironolactone is usually mild, and the drug is well tolerated in the doses usually prescribed for female pattern hair loss. Most common side effects include:
NoteThe intake of spironolactone is contraindicated in pregnant women and those suffering from kidney diseases.
Because of the side-effects mentioned above, spironolactone should not be started without consulting a physician. What is more, in the first few months of treatment, regular monitoring of electrolytes and blood pressure is recommended.
Current therapy options for women’s hormonal hair loss are limited. FDA-approved systemic therapy with finasteride is neither as safe nor as effective in females as in males.
This gap is very elegantly filled by spironolactone. One of the highest prescribed off-label therapy for female pattern hair loss, spironolactone, as a monotherapy or combination with other therapies, is one of the most effective and well-tolerated options for hair loss therapy in women.
The only caution that needs to be exercised is that it should be taken only under a physician’s directions and with regular monitoring.