Hives After Laser Hair Removal: How to Treat a Rash

Are you dealing with hives after a laser hair removal treatment? While it can be concerning and unpleasant, getting a post-treatment rash isn’t unheard of. It’s usually not a major cause for concern, either. 

In this post, we explain why laser hair removal sometimes causes hives, how long you can expect the reaction to last, and how to help it fade more quickly.

Can Laser Hair Removal Cause Hives? 

Yes, laser hair removal can cause hives. Also known as “urticaria”, this is a type of rash that occurs after the skin has been exposed to irritants or allergens. It’s basically your immune system overreacting to the treatment you just experienced. 

Getting hives after laser hair removal is not very common, but it’s also not a big deal in most cases. A 2012 study at a clinic that served over 13,000 patients identified 36 who developed hives severe enough for clinical follow-up. 

According to the study, hives or rashes are more likely to occur in patients who have other allergies, such as hay fever. The areas most prone to developing hives are the legs, followed by the bikini area and underarms.

Why Do I Get Hives After Laser Hair Removal? 

Getting hives happens when your body’s immune system reacts to the laser’s effects as if they were an allergen. Lasers use targeted heat to destroy the hair follicles and prevent hair growth. 

According to the researchers who published the 2012 study, the follicular damage is likely responsible for triggering a hypersensitivity reaction. The immune system activates and releases histamine, which causes hives to form in the treated area. 

Many practitioners call this kind of post-laser rash a “histamine reaction”, although the term isn’t used in scientific literature. Some people get hives after every laser session, while for others, it only happens randomly.

Allergy to Numbing Creams or Sprays

In some cases, hives can occur as a reaction to topical numbing products or to cryogen coolant sprays. With both, it’s easy to perform a patch test either at home or at the laser clinic. 

If you’re a client at SEV, rest assured that the cooling device we use only emits cold air, without cryogen.

We also recommend our clients avoid using numbing creams for laser hair removal, and not just because of the allergy risk. Numbing creams dull your ability to feel if the laser is too intense for your skin, and also cause slight swelling that can hide the hair follicle and compromise efficacy.

How to Prevent Hives from Laser Hair Removal

If it’s your first time getting laser hair removal, the best way to prevent developing hives is to follow all of your provider’s pre- and post-care instructions. 

In particular, avoid hot or damp environments and intense activities that raise your body temperature after treatment. This includes everything from jacuzzis and saunas to even wearing tight clothes that trap heat.

 Additionally, avoid using any topical products other than aloe vera and sunscreen for the first 24 hours after treatment. 

If you’ve had laser hair removal before and you know that you’re prone to histamine reactions, speak to your doctor or nurse about OTC or prescription treatments. 

At SEV, we typically don’t recommend getting lasered while taking allergy medications with the potential to cause photosensitivity. However, if cleared by your doctor beforehand, some anti-inflammatory and antihistamine medications can be effective for preventing hives.

What to Do if I Get Hives After Laser?

So you have hives or a rash after a laser hair removal treatment – here’s how you can relieve some of the symptoms, and help it fade faster. 

Cold Compress

A cold compress can help with the discomfort or itchiness often caused by a histamine reaction. It’ll also help if you’re dealing with simple post-treatment inflammation. 

There are many ways to make a cold compress: You can dip a towel in an ice bath, or fill a plastic bag with ice cubes and then wrap it in a towel. Don’t put ice or ice packs in direct contact with your skin, as that may lead to an ice burn or frostbite.

Hold the cold compress against your skin for about 10 minutes at a time, on and off throughout the day. 

OTC Treatments 

Hydrocortisone cream is a topical steroid with an anti-inflammatory effect. It can help with post-laser redness, itchiness, and swelling, whether it’s histamine-related or not. Don’t use it before laser hair removal, and don’t use it for more than 7 days after the treatment unless directed otherwise by your doctor.

Alternatively or in addition to cortisone, you can take an oral antihistamine like Benadryl. 

When to See a Doctor 

You should see a doctor if your symptoms are severe or don’t show signs of fading within a few days of treatment. Seek medical attention immediately if you experience throat swelling, fever, signs of infection, or trouble breathing.

How Long Until the Rash Goes Away? 

In most cases, rashes after laser hair removal go away within 72 hours, especially with additional treatment. However, redness or marks from the rash may last longer, up to 1 month, depending on the severity of the original reaction. 

Distinguishing Hives vs Follicular Edema

It can be difficult to distinguish between common laser hair removal side effects like perifollicular edema (i.e., short-occurring redness and swelling only at the hair follicle) and hives. 

The main difference is that follicular edema looks like small bumps that only surround the hair follicles. Hives are a little larger with greater areas of swelling. Follicular edema usually feels a little tender and painful, while hives can also feel itchy. 

While it is nice to know what you’re facing, keep in mind that treatment is often similar, and both side effects usually resolve on their own. 

Post-Laser Rash: Bottom Line 

Getting a rash or hives after laser hair removal is surprisingly common. The laser’s effect on your hair follicles triggers the body’s immune system, causing temporary inflammation and itchiness. 

The good news is that hives will usually disappear on their own within a few days. We included a few treatment options in this article to help you find relief even sooner. That said, if your hives are unusually severe, long-lasting, or you’re experiencing additional symptoms, please seek medical care right away!