Minoxidil for Hair Growth: Minoxidil Side Effects, Benefits, & More

Also known by the brand name Rogaine®, minoxidil is one of the most widely used hair loss treatments on the market. But minoxidil side effects and the different ways to apply it should be considered before starting the medication.

Ahead, we’ll discuss how to use minoxidil for hair loss, including why millions of people use it, the different topical minoxidil formulations, oral options, and potential minoxidil side effects so you know exactly what to expect.

Minoxidil is the generic version and active ingredient in Rogaine, a brand-name product. They basically work in the same way, as the active ingredient is minoxidil.

Minoxidil is a well-known hair loss medication used to stimulate the hair growth cycle and slow down hair loss.

Current research suggests minoxidil works in two ways:

• It stimulates blood circulation in the scalp, ensuring hair follicles have a constant supply of nutrients and oxygen.

• It moves hair follicles into a state of active growth, meaning hair grows for a longer period.

Your hair follicles contain an enzyme called sulfotransferase. When you apply topical minoxidil, the enzyme converts it to minoxidil sulfate.

Minoxidil sulfate moves hair follicles into the anagen phase of the hair growth cycle, meaning hair starts growing instead of resting. It also extends the anagen phase, so hair follicles spend more time growing before each hair sheds from your scalp.

As for stimulating blood flow, research suggests minoxidil dilates blood vessels on the scalp. This can improve the supply of nutrients your follicles need to build strong, healthy hair strands.

A 2004 study published in the Journal of the American Academy of Dermatology followed nearly 1,000 men who used a 5% topical minoxidil solution for hair growth. After a year, 84 percent of participants saw positive results.

There are two forms of minoxidil treatments: topical minoxidil and oral minoxidil.

Topical minoxidil comes as a foam or liquid solution. You apply it directly to your scalp where there’s hair loss, up to twice a day for optimal hair growth.

At the moment, the U.S. Food and Drug Administration (FDA) has only approved topical minoxidil for the treatment of male pattern hair loss.

Topical minoxidil can be used to treat multiple forms of hair loss, including:

• Androgenetic alopecia (male pattern baldness)

• Chemotherapy-induced hair loss

• Traction alopecia (hair loss due to tension at the roots)

• Telogen effluvium (stress-induced hair loss)

Another bonus? Unlike finasteride, another well-known hair loss treatment, topical minoxidil is available over the counter — so you don’t need a prescription to get your hands on it.

Oral minoxidil, on the other hand, is a vasodilator medication for hypertension (high blood pressure).

While oral minoxidil is FDA-approved for treating high blood pressure, it’s not approved for hair loss.

However, low-dose oral minoxidil can still be used off-label to treat hair loss. (Off-label means a medication is prescribed for something it’s not FDA-approved for.)

Since topical minoxidil is a widely used, thoroughly tested medication, its side effects are well known. For the most part, they’re also considered manageable.

Topical minoxidil in foam or liquid form is used much more often than oral minoxidil. However, in some cases, your healthcare provider may suggest the oral version, which has slightly different risks.

Side Effects of Topical Minoxidil

Side effects of minoxidil topical vary in part due to the formulation. But the most common topical minoxidil side effects are:

• Skin irritation at the application site

• Scalp itchiness

• Slight burning sensation

• Skin rash

These side effects are usually mild and temporary.

Sometimes, adverse effects are caused by other ingredients commonly used in minoxidil formulas, like propylene glycol (an alcohol). If your skin is sensitive to these substances, you might notice irritation after applying minoxidil.

If you experience a bad reaction, let your healthcare provider know. They might suggest using a different formulation that’s less likely to cause scalp conditions.

Less common side effects of topical minoxidil include:

• Allergic reactions

• Temporary hair shedding

• Unwanted hair growth

• Red bumps

• Acne breakouts

• Facial swelling

• Headaches

You might also have specific side effects if you use minoxidil excessively — like if you apply it more than twice a day or use too much of it on your scalp.

Potential side effects associated with excessive minoxidil use include:

• Dizziness or lightheadedness

• Swelling on the face, ankles, stomach, or hands

• Changes in body weight, such as weight gain

• Difficulty breathing when lying down

• Chest pain or a rapid heartbeat

If you develop any of these adverse reactions after using minoxidil, contact a healthcare professional as soon as you can for medical advice.

Side Effects of Oral Minoxidil

Like topical minoxidil, oral minoxidil can cause side effects. These include:

• Hypertrichosis (excessive body hair growth)

• Tachycardia (fast heart rate)

• Dizziness that comes and goes

• Fluid retention

• Hair shedding

• Heart issues

• Headaches

• Nausea or vomiting

• Skin rash

• Acne

If you’re prescribed oral minoxidil to treat hair loss and develop side effects, be sure to tell your healthcare provider.

Minoxidil is a safe, widely used medication for hair regrowth, with numerous large-scale studies showing that serious side effects are uncommon.

For instance, one review published in the journal Drug Design, Development and Therapy noted that minoxidil is generally considered an “effective and safe” treatment for hair loss.

A separate study published in the Journal of the American Academy of Dermatology looked at the effects of topical minoxidil in men with pattern hair loss over a 48-week period of clinical trials. It found that the medication was well tolerated without any evidence of systemic effects.

Millions of people use minoxidil, and most don’t experience any negative effects.

One last important note for the gents worried about how minoxidil might affect intimacy: Minoxidil doesn’t cause sexual side effects. However, breastfeeding women should avoid minoxidil without first talking to a dermatologist or another healthcare professional.

One benefit of topical minoxidil is that it doesn’t seem to interact with other drugs or supplements. This means you can use topical minoxidil to treat a receding hairline with confidence in its safety, even if you’re currently prescribed other medications.

Oral minoxidil is another story. It shouldn’t be used alongside certain medications, including:

• Diphenhydramine (Benadryl®)

• Bupropion (Wellbutrin®)

• Alprazolam (Xanax®)

• Medications for hypertension (high blood pressure), including diuretics like furosemide (Lasix®), vasodilators, and beta-blockers

Whether you opt for topical or oral minoxidil, it’s best to tell your healthcare provider about any other meds or supplements you’re taking. You should also let them know about any heart failure or cardiovascular history.

Minoxidil is a simple medication to use.

If you use a minoxidil topical solution (liquid), follow these steps:

• Make sure your hair is completely dry.

• Fill the dropper with 1 milliliter (mL) of minoxidil solution.

• Apply the solution to the affected areas of your scalp.

• Using your fingers, gently massage it into your scalp.

• Wash your hands thoroughly with soap and warm water.

If you use minoxidil foam, follow these steps:

• Make sure your hair is completely dry.

• Dispense half a capful of foam onto your fingers.

• Massage the foam into areas of your scalp with noticeable hair loss.

• When you’re done, wash your hands thoroughly with soap and warm water.

After you’ve applied minoxidil solution or foam to your scalp, wait at least four hours before covering or washing your hair.

It’s crucial to use minoxidil regularly. Typically, you’ll apply it once or twice a day, depending on the instructions you’re given.

If you forget to apply it, no worries — just carry on with your next dose as normal. Don’t apply extra minoxidil to make up for a missed dose, as this can lead to minoxidil side effects.

Minoxidil can stain clothes, bath linens, bedding, and fabric upholstery. That’s why you need to wash your hands thoroughly after applying it — and make sure it’s totally dry before letting your head touch any fabric.

Our guide to applying minoxidil for hair growth has more details on this topic.

It’s best to keep minoxidil in a room-temperature environment away from excess heat and moisture. So don’t put it in your shower, where it’ll frequently get warm and wet.

Also, keep minoxidil out of reach of children and pets. Consider putting it on a dresser or medicine cabinet, far out of reach and sight.

Since minoxidil works best with once- or twice-daily application, it’s good to have a visual reminder to use it every day. So set a reminder on your phone or keep it somewhere you’ll see it.

Finasteride is another FDA-approved hair loss treatment sold under the brand name Propecia®.

Unlike minoxidil, finasteride stops your body from converting testosterone into DHT (dihydrotestosterone), the androgen (male sex hormone) that causes male pattern baldness.

For this reason, finasteride is fantastic for treating male pattern hair loss.

The best thing about it? You can safely use finasteride and minoxidil at the same time. In fact, finasteride and minoxidil are a very effective combination for male pattern hair loss.

In one study, researchers found that finasteride and minoxidil were more likely to produce improvements when used together than when either medication was used on its own.

Out of 428 participants, 59 percent of men with pattern hair loss who used minoxidil on its own and 80.5 percent who used finasteride showed improvements after 12 months.

In comparison, 94 percent of men who used both medications showed improvements after a year.

It’s worth noting, though, that finasteride only works for male pattern baldness — not other types of hair loss.

If you already use minoxidil, you can add oral finasteride to your routine. Or try our topical finasteride & minoxidil spray, which brings together the best of both worlds to promote healthy hair growth.

Check out our guide to DHT and male pattern hair loss for more details on how DHT affects hair follicles.

Minoxidil hair loss treatments are highly effective and safe — a couple of reasons why it’s a nonprescription medication. Topical minoxidil is a great first choice if you’re starting to notice the early signs of hair thinning.

Here’s the bottom line on minoxidil for hair:

• Minoxidil works. Plenty of research supports the use of minoxidil therapy for hair growth. It’s effective at slowing down many forms of hair loss.

• There are a few potential minoxidil side effects. The most common side effects of topical minoxidil are typically mild and not long-lasting. While serious side effects can occur, they tend to be rare. Still, keep your eyes peeled for any adverse effects.

• Minoxidil can be combined with finasteride. This is a good option for male pattern hair loss. Not only is this combo safe, but it’s also highly effective.

Interested in using minoxidil to stop hair loss and increase your hair count? We offer a range of evidence-based hair loss medications online, including minoxidil solution and minoxidil foam.

Although you don’t need a prescription for topical minoxidil, you may still find it helpful to get professional insights. We can connect you with a healthcare provider who can assess your hair loss and help you figure out the best way forward.