Laser hair removal usually hurts most at the first session and less as the hair thins out. In one underarm study, average pain scores dropped from 3.5 at the first session to 1.69 by the third. With less hair left, there's simply less for the laser to heat up.

Coarse, dense hair tends to sting more than fine hair, and a quick burst of cooling spray just before each pulse can take the edge off. In this article, we'll cover what the first session feels like, why later sessions get easier, how hair thickness changes the sting, what lowers it, which reactions are normal and how to fit treatment around a trip.

Quick summary

• Laser hair removal stings most at the first session, while the hair is thickest, and the same area usually hurts less once the hair thins.

• What it feels like: many people compare each pulse to a warm pinprick or a rubber band snapping against the skin.

• In a small study of 10 people, a longer burst of cooling spray right before the laser meant less pain.

• Normal reactions: redness, swelling and discomfort usually settle within 1 to 3 days.

How Much Does Laser Hair Removal Hurt the First Time?

Expect a quick, sharp sting with each pulse that fades almost as soon as it lands. Many people describe it as a warm pinprick or a rubber band being snapped against the skin*. It doesn't build into a steady ache; it comes and goes with each flash of light.

*Based on patient guidance from the American Academy of Dermatology (AAD).

How long you'll feel it depends on the size of the area. The upper lip takes just minutes, while a large area like the back or legs can take more than an hour. If you're nervous about a big area, it's worth knowing that before you book.

Here's why the first session stings the most. The laser's light is absorbed by the dark pigment inside each hair and turns into heat, which weakens the hair root (follicle*). The thicker and denser the hair in a spot, the more heat builds up with every pulse, and the more you feel it.

*Follicle: the tiny pocket in the skin that each hair grows out of.

Does Laser Hair Removal Hurt Less After Each Session?

Yes, in most cases the sting eases as the hair thins. In a study of 48 underarms treated 3 times, 1 month apart, with an alexandrite (755 nm) laser, hair counts and pain scores dropped together. In the group treated around ovulation, average pain went from 3.5 at the first session to 3.06 at the second and 1.69 at the third.

Hair in that same group fell from 41.8 hairs per 4 square centimeters before treatment to 8.6 after the third session. Less hair means less pigment soaking up the light, so there's less heat to feel. Keep in mind that this study looked only at underarms and only one type of laser, so its numbers won't carry over exactly to other areas. Results differ from person to person, but your first session isn't a preview of every session to come.

The same study also compared timing within the menstrual cycle. People treated during their period rated the pain a little higher, though the gap was small enough that it could have been chance. Hair reduction was the same at every point in the cycle. So if you tend to feel pain more during your period, booking around that week won't cost you results.

Does Thick, Coarse Hair Make Laser Hair Removal Hurt More?

Coarse hair holds more heat, so the same area can sting more on someone with thick hair. The GentleMax Pro Plus has two wavelengths, 755 nm and 1064 nm, which reach different depths and suit different kinds of hair. With men, I first ask about any past hair removal and check whether the hair is especially thick. If earlier sessions didn't clear the hair well, or the hair is very coarse, I treat the roots as sitting deeper and mix in 1064 nm.

Many people worry that adding 1064 nm will hurt more. A Korean study tested this on 41 adults by treating one side of the body with 755 nm alone and the other side with 755 nm and 1064 nm fired together. Everyone had 3 sessions, 4 weeks apart. The combined side hurt slightly more at the second session only, and satisfaction was about the same on both sides.

Hair on the combined side also got thinner than on the 755 nm side, while the drop in the number of hairs was similar. That study used a different manufacturer's device, not the GentleMax Pro Plus, so treat its numbers as a rough guide rather than a forecast for your own sessions. How much difference you notice depends on your hair and skin.

What Actually Takes the Sting Out During Treatment?

A short burst of cold cooling spray hits the skin a split second before each laser pulse and chills the surface. In a small study with a 755 nm laser, researchers varied that burst from 0 to 100 milliseconds. Longer bursts generally meant less pain, and even 20 milliseconds helped every patient.

That study included only 10 people with medium to darker skin, so it isn't enough on its own to set the spray time. I decide how long the burst runs after looking at your skin tone and your hair, since the right balance of comfort and skin protection differs from person to person.

Fortunately, cooling isn't the only lever. Pain-relief methods that include skin cooling have generally done better than no relief at all, though the research comparing them is limited and the methods vary widely. After treatment, a cool compress can soothe any lingering warmth or sting.

Laser Hair Removal Side Effects: What's Normal and When to Call

Redness, swelling and discomfort are common and usually settle within 1 to 3 days. The treated skin often looks like a mild sunburn, and most people go straight back to their day. While it heals, keep the area out of direct sun and skip tanning.

These are different. Don't wait it out if you notice any of them; contact your provider right away:

• Blisters, or skin that weeps or oozes

• Warmth and swelling that keep getting worse after 3 days instead of easing

• A cold sore (herpes) flare-up around the lips

• Skin that turns noticeably lighter or darker than the area around it

In these cases, let the clinic know before your session, since it may be better to postpone treatment:

• You've recently tanned

• You scar easily or have had a keloid (a raised, overgrown scar)

• You've taken or are taking isotretinoin, a prescription acne medicine

Fitting Laser Hair Removal Into Your Travel Itinerary

Unless you've had sedation that day, there's no need to postpone your flight home after a laser hair removal session.

It also helps to know what one visit can do. Some treatments, such as fillers, change your shape the same day. Laser hair removal works more gradually: hair sheds and thins over the weeks after each session, and clearing an area takes a series of sessions rather than a single visit.

Once you're home, you can send photos through the consultation button on this page if you have questions about how your skin is settling. If you see blistering, oozing or redness that keeps spreading, see a local doctor first rather than waiting for a reply.

The Bottom Line: Ask Which Wavelength Fits Your Hair

Before you decide, ask whether your hair calls for 755 nm alone or a mix with 1064 nm. That one answer helps you picture how the early sessions may feel, especially if your hair is coarse or past treatments didn't work well. Like any procedure, laser hair removal comes with trade-offs, and the right setting depends on your hair and your skin.

Beautystone is a clinic in Seoul's Hapjeong area, and you can reach us through the consultation button on this page. In your first message, include the areas you'd like treated, any hair removal you've had before and the dates you're hoping for.

Sources

• Hair counts and pain scores over 3 underarm sessions, and timing in the menstrual cycle — Aesthetic Surgery Journal, 2024

• A 41-person Korean study comparing 755 nm alone with 755 nm plus 1064 nm — Lasers in Medical Science, 2026

• How the length of the cooling spray changed pain with a 755 nm laser — Lasers in Surgery and Medicine, 2002

• A review of non-invasive pain relief for skin laser procedures — Journal of the European Academy of Dermatology and Venereology, 2017

• What laser hair removal feels like, recovery, timing and side effects — AAD

• What to tell your doctor and how to protect your skin from the sun — AAD