Medically reviewed by Vicky Davis, FNP
Written by Our Editorial Team
Last updated 5/21/2021
Call it vanity, but one of the last things any woman wants to experience is the loss of her hair.
Unfortunately, a lot of women experience this condition. In fact, nearly half of the population of women—around 40%—will experience female pattern hair loss at some point in life, and it’s the most common way to lose your hair.
If (like many women), you’ve observed hair thinning around the crown of your head, you’re probably familiar with topical minoxidil (brand name Rogaine), the only FDA-approved treatment for hair loss in women. It is also used for alopecia areata and other forms of hair loss.
You’re also most likely aware that it comes in 2% and 5% formulations. Yet when it comes to: minoxidil 2 vs. 5: which works better and why?
Below you’ll find information on how minoxidil works to encourage hair growth, along with which percentage of this treatment might work best for you.
Finally, learn about minoxidil 2 vs. 5 side-effects you may experience when using this medication.
The jury is out. While the exact mechanism for how minoxidil works remains unclear, it’s known that it operates as a vasodilator to encourage hair growth.
This means the medication encourages blood vessels–especially those on the scalp—to widen and permit more blood to flow. This increases the supply of oxygen and nutrients which are necessary for hair growth.
Minoxidil also helps boost hair growth by increasing the hair follicle size, which leads to the production of thicker hairs.
To ensure your hair grows to an acceptable length and density, minoxidil is also able to elongate the anagen phase of the hair cycle, which is the stage during which the hair follicle grows.
It does this by shortening the telogen or resting phase of the hair.
Minoxidil is available as a solution, foam and oral tablet, yet while the oral form has shown promise in stimulating hair growth, it is yet to be recognized by the FDA for approved use, and is more popularly reserved for managing cases of severe hypertension.
Minoxidil gets all the props for being the only FDA-approved hair growth treatment for women. But while this is correct, it isn’t 100% accurate.
At present, cool approval status is reserved only for the 2% minoxidil solution and foam, as well as the 5% foam formulation. And while women can apply the 5% solution, it will be considered off-label use.
At 2% and 5%, these concentrations show minoxidil at different strengths. But will this difference matter when attempting to fill out the balding sections of your hair?
In a 32-week study to determine how effective a topical minoxidil 2% solution was in treating female pattern hair loss, researchers examined results from 256 women.
On average, the women who used the 2% minoxidil solution found an increase in hair growth. A whopping 60% of the study participants who used minoxidil reported new hair growth, with about 20% of that as moderate, and 40% minimal.
In general, the 2% minoxidil solution was found to be more effective at improving hair loss when compared with a placebo.
Researchers conducted a similar test examining the safety and effectiveness of a 5% minoxidil foam for treating female pattern hair loss.
The study included 404 women who were given a daily application of the foam to treat their condition.
After 12 weeks, not only had the foam improved hair regrowth, it encouraged more hair across the scalp, and increased hair density.
Another 48-week trial compared the effects of 5% topical minoxidil against a 2% formulation to determine how well the medication strengths worked.
The study was split between 381 women with female pattern hair loss.
Researchers found that 5% minoxidil seemed to be better suited for promoting hair growth and increasing hair count.
Even so, 2% topical minoxidil was found to be superior to the placebo treatment for improving hair growth, and both concentrations were well-tolerated by the women.
The strength of the 5% concentration was also confirmed in another test that lasted 24 weeks.
In this study, 113 women with FPHL were divided into groups instructed to apply a once-daily 5% minoxidil topical foam, while others administered the 2% formulation twice daily.
Despite the lower application frequency, the once-daily 5% solution was found to be just as effective for stimulating hair growth when compared to its 2% counterpart.
In sum, while both treatments are undoubtedly effective at improving hair growth in women—the 5% minoxidil formulation may be the preferred option, especially for more severe cases of hair loss.
While minoxidil may help your hair fill out nicely, it can also come with some side effects. It’s important to know the medication is typically safe and well-tolerated, yet those people who have used minoxidil to manage hair loss have reported the following side effects:
This happens where telogen-phase hair falls off, making way for new anagen hairs to be produced. It's usually a temporary setback.
Topical minoxidil usage may sometimes lead to redness on the skin, or a burning sensation.
Minoxidil can worsen cases of seborrheic dermatitis, and it has been known to cause scalp irritation.
In some cases, when skin comes in contact with minoxidil, it can lead to an outbreak of allergic contact dermatitis.
This medication has also been known to cause itchiness in portions of the skin it comes in contact with.
If you find that you're sensitive to minoxidil or its ingredients, or you experience side effects like itchiness, you might be better off trying an alternate treatment for hair growth.
Likewise, if you have a little one on the way, or are already in the process of breastfeeding, it's best to stay on the safe side and use milder forms of hair growth treatments. You can learn more about the effects of minoxidil breastfeeding in this guide.
As a topical solution or foam, minoxidil is one of the most trusted medications when it comes to encouraging hair growth in women.
The 2% and 5% minoxidil formulations both get the job done when you're looking to patch up the thinning or balding sections of your hair.
However, according to research, you may have a better, and quicker chance of improving your hair’s appearance with the 5% dosage.
And as always, it’s a good idea to check in with a certified healthcare professional to explore your best options.