By Editorial TeamSo, you’re looking for consistently smooth underarms and want to do something about pigmentation. It’s a common goal that sends people down the rabbit hole of hair removal methods. Intense Pulsed Light (IPL) seems like it could tackle both hair growth and skin tone, but you have to know what you’re doing. Can it really get the job done without creating bigger problems?
Key Takeaways
- You absolutely must do a patch test before starting any IPL treatment. This lets you see how your skin reacts and helps you dial in the right settings, which is especially important for sensitive underarm skin.
- For IPL to work well on your underarms, you need to stick to a consistent schedule, usually zapping the area every two to four weeks at first, so you can catch hairs in their active growth phase.
- To avoid creating dark spots, always use a device that lets you adjust the power level and be obsessive about using a broad-spectrum SPF 30+ sunscreen on the treated skin.
- Picking an IPL device that has a cooling feature built-in, or just using a cold pack on your own, will make the process way more comfortable and less likely to cause a bad skin reaction.
1. Evaluate Your Skin Type and Hair Color for IPL Suitability
Before you do anything else, you have to figure out if IPL is even right for you, and that comes down to your skin and hair color. The technology works by targeting the melanin (the pigment) inside your hair follicles. That means it works best when there’s a big contrast, in other words, for people with darker hair and lighter skin. If your hair is very light blond, red, or gray, there just isn’t enough melanin for the device’s light to grab onto, making the treatment pretty ineffective. On the other hand, people with darker skin tones have a lot of melanin in their skin itself, which creates a higher risk of burns, hyperpigmentation, or even light spots (hypopigmentation) if the power setting is too high.
Most of the good at-home IPL devices, like the Philips Lumea Prestige or the Braun Silk-expert Pro 5, come with a built-in skin tone sensor. This sensor will either adjust the intensity for you or just refuse to flash if it detects a skin tone that’s too dark to be treated safely. This feature is a critical safety mechanism. Always check the manual for the device’s specific chart showing compatible skin tones and hair colors before you even think about starting.
Pro Tip: Conduct a Thorough Patch Test
Before you go all-in on your underarms, you must perform a patch test on a small, hidden spot. Use the device on its lowest setting as instructed, then wait a full 24 to 48 hours. You’re looking for any bad reactions, things like serious redness, blisters, or pain that doesn’t go away. This step isn’t optional, especially for a sensitive area like the underarms, which can get irritated much more easily than the skin on your legs. I’ve seen too many people skip this and end up with a mess they regret.
2. Prepare the Underarm Area Carefully
Good prep is what makes the treatment safe and effective. Start by washing your underarms completely. Use a simple, gentle soap and water to get rid of every trace of deodorant, antiperspirant, lotion, or oil. Any residue left on the skin can mess with how the IPL light is absorbed, which can lead to uneven results or even skin irritation and burns. Once you’re done washing, pat the skin totally dry.
Next up is shaving, and it’s a big one. IPL needs to target the hair follicle below the surface, not the hair you can see. Shaving right before your session lets the light energy go straight to the follicle, which gives you the best results and avoids the risk of burning the surface hair. Whatever you do, don’t wax, epilate, or pluck. Those methods yank the whole follicle out, so the IPL has nothing to target. Shaving about 12 to 24 hours before you use the device is the sweet spot, as it gives your skin a little time to calm down while keeping the hair short enough for the treatment.
Common Mistake: Not Shaving or Using Other Hair Removal Methods
If you don’t shave, or if you decide to wax or pluck instead, you’re going to get bad results and you’re more likely to irritate your skin. When there’s hair on the surface, the IPL energy gets wasted on that visible hair, leading to a burnt smell, maybe some skin irritation, and much less energy actually getting down into the follicle. This makes the whole treatment a lot less effective.
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Getting the setting right is everything. Most at-home IPL devices give you a range of intensity levels, usually from 1 (the lowest) up to 5 or even 10 (the highest). The right setting for you is based on your skin tone and hair color which you should have a good idea of after your patch test and from checking the device’s sensor. Because the underarms can be more sensitive than other areas, it’s smart to start with a lower setting than you might use on your legs, for instance.
If you have a Fitzpatrick Skin Type from I to III with dark hair, you can probably work your way up to a higher setting over a few sessions as long as your skin is handling it well. Just pay close attention to how it feels. A device like the Philips Lumea Prestige, for example, often suggests starting at a medium intensity (like a 3 or 4) for the first few treatments on compatible skin types, then adjusting from there based on your comfort and the results you’re seeing. Make sure the device’s glass window is pressed flat against your skin for every flash to get even light coverage and avoid patchy results.
4. Execute the IPL Treatment Methodically
Okay, your skin is prepped and your setting is chosen, time to get started. Press the device’s treatment window flat and firm against your skin. Most won’t flash unless they have full contact. Hit the button, you’ll see the bright flash, and then immediately slide the device to the next spot right beside the one you just did. A little bit of overlap is fine, but don’t flash the exact same spot more than once during a session. That’s just asking for overheating and irritation.
The underarm area is curved and can be tricky to get full contact on. So, should you just rush through it? No, take your time and adjust the angle of the device as needed to keep it flush with your skin. A lot of people find it easier to mentally divide the underarm into a grid and work through the sections one by one to make sure they don’t miss anything. The whole thing for both underarms should only take a couple of minutes, especially with the newer devices that flash quickly.
Pro Tip: Use Cooling Features
Some of the fancier IPL devices, like certain models of the Iluminage Touch, have cooling tech built right in to make the treatment more comfortable. If yours doesn’t have that, you can improvise. Try holding a cold pack on your skin for a few seconds right before and after you flash each spot. This can really help with the warm sensation, especially on underarms which are prone to feeling hot and sweaty anyway.
5. Implement Post-Treatment Care and Monitor Progress
After you finish your session, your underarms might feel a bit warm and look slightly red, kind of like a very mild sunburn. This reaction is normal. Slather on a soothing, fragrance-free moisturizer like a pure aloe vera gel or a gentle lotion made for post-treatment care to help hydrate the skin and calm it down. For at least 24 hours, you need to avoid anything that could irritate the skin further, so no harsh scrubs, hot showers, saunas, or tight-fitting clothes.
And you have to protect the area from the sun. IPL makes your skin more sensitive to UV light, which can cause hyperpigmentation. If you’re going to wear sleeveless tops or otherwise expose your underarms, you must apply a broad-spectrum sunscreen with an SPF of 30 or higher. For IPL to work, you have to be consistent. Most device manuals recommend treating the area once every two to four weeks for the first phase (usually 4-12 treatments), and then you can switch to maintenance sessions every month or two as needed. Keep a close eye on your skin after every single session. If you see anything unusual or severe (like blistering, redness that lasts for days, or real pain), stop using the device immediately and call a dermatologist.
Common Mistake: Irregular Treatment Schedule
One of the main reasons people get frustrated with their IPL results is because they don’t stick to a consistent schedule. Hair grows in different phases, and IPL only works on hairs in the anagen (or active growth) phase. When you do treatments at random times, you’re constantly missing that window of opportunity, which means you’ll see results much more slowly and will have to do way more sessions in the long run. Follow the schedule in your device’s manual.
6. Address Underarm Pigmentation Risks
While IPL can sometimes help with hyperpigmentation because it targets melanin, it can also make pigmentation worse if you don’t use it correctly. This is especially true for people with naturally darker skin tones or for anyone who lets the sun hit the treated area. The intense light can overstimulate your melanin-producing cells (the melanocytes), causing what’s known as post-inflammatory hyperpigmentation (PIH).
To keep the risk of pigmentation issues low, you have to follow the skin tone guide for your device without exception. If you have a darker skin tone (Fitzpatrick Type IV or above), you should look for devices made specifically for you, or better yet, see a professional who uses laser systems with longer wavelengths that are safer for skin with more melanin. And always, always do a patch test with the lowest power setting that seems effective. If you see any skin darkening after a treatment, stop right away and talk to a dermatologist. Using a broad-spectrum SPF 30+ sunscreen is non-negotiable, even on cloudy days, especially when you’re just starting out with treatments.
Getting a handle on underarm pigmentation also means looking beyond just IPL. Things like friction from your clothes, ingredients in some deodorants, and even hormonal shifts can cause skin to darken. While IPL can help with the pigmentation that’s tied to the hair follicles themselves, you’ll get a more complete solution by also addressing those other causes with better skincare (like using a gentle exfoliant or an aluminum-free deodorant) and other lifestyle changes.
To get good at using IPL on your underarms, you need a combination of good prep, careful technique, and solid aftercare. If you follow these steps and pay attention to what your own skin is telling you, you can get much smoother skin and lower the risks of pigmentation changes. If you’re still exploring your options, it’s a good idea to check out the waxing vs. IPL debate to see which one really fits your needs. Learning about proper post-wax aftercare can also give you some good ideas for skin recovery that apply to IPL use, too. And if you’re thinking about the cost and convenience of it all, looking into reusable IPL devices can give you a better picture of the long-term savings.
How long until I see results from IPL on my underarms?
Most people start seeing less hair and finer regrowth after 3 to 4 treatments done consistently, which usually takes about 6 to 8 weeks. For a really big reduction in hair, you’re typically looking at 8 to 12 sessions.
Can IPL make my underarm pigmentation worse?
Yes, it’s possible. If you use it the wrong way or on a skin type that isn’t compatible, IPL can definitely make underarm pigmentation worse and cause hyperpigmentation. The risk is higher for people with darker skin or if you expose the area to sun without sunscreen.
Is it safe to use IPL on sensitive underarm skin?
IPL can be perfectly safe for sensitive underarm skin, but only if you take the right precautions. That means doing a patch test, using the correct intensity setting for your skin, and following a good aftercare routine. Your comfort is the priority. Turn down the intensity if you feel any irritation.
How often should I be using IPL on my underarms?
When you’re starting out, most at-home IPL device instructions will tell you to treat the area once every two weeks for the first four to six sessions. After that initial round, you can usually switch to maintenance treatments every four to eight weeks, just depending on how fast your hair starts to grow back.
What do I need to avoid after an underarm IPL session?
For at least 24 to 48 hours after an IPL session, stay out of the sun, and avoid hot showers, saunas, swimming pools with chlorine, and any harsh skincare products or scrubs on the area. Just apply a gentle, fragrance-free moisturizer.
