Lash Serum Side Effects — The Dark Truth You Must Know

By now, you already know that not everything is sunshine and roses with lash serums. The truth is, yes you may very well experience side effects from using an eyelash growth serum.

There I said it.

That’s why this article is so important. You deserve to know exactly why lash serums may be bad for you before deciding if the benefits are worth the risks.

Now, it doesn’t mean you’ll experience every side effect (or any of them for that matter) that I’m about to mention. Most people don’t in fact. But everyone is different so I think it’s best to be aware of all possibilities.

Let’s dive in!

What Are the Side Effects of Lash Serums?

The truth is, lash serums can damage your lashes and your eyes. They often use compounds known as prostaglandin analogs to stimulate lash growth and darken your lashes. While prostaglandin analogs can enhance your lashes, they can also cause hyperpigmentation, as well as irritation, and even orbital fat loss.

The most common prostaglandin analog names you’ll find on ingredient labels are:

• Bimatoprost
• Isopropyl cloprostenate
• Isopropyl phenyl hydroxypentane
• Dihydroxy cyclopentyl heptane
• Dechloro dihydroxy difluoro ethylcloprostenolamide
• Latanoprost

According to The Mayo Clinic, bimatoprost carries a wide range of unwanted side effects. They list them by “less common” to “most common”. You can see the list here.¹

Fun fact: Prostaglandin analogs were typically used to treat glaucoma, and it was simply by coincidence that medical professionals discovered one surprising side-effect of the chemicals: long and luscious lashes!

Having said that, prostaglandin analogs are not the only potential culprit, but they’re definitely one of the most important ones to watch for.

Now, let’s explore some of these side effects in more detail and distinguish myths from reality.

1- Eye Irritation, Redness & Itching

One of the most common side effects of a growth serum is irritation. Redness, itchiness, watery eyes, and bloodshot eyes can be pretty commonplace.

In fact, one study showed that amongst those who discontinued using their over-the-counter lash serum, 40% cited “side effects” as their reason for stopping.²

Irritation can include anything from redness to sensitive eyes, but some users can even experience blurred vision. This occurs when certain prostaglandin analogs come into contact with the eyes and reduce intraocular pressure, which can cause vision problems.

I’m sure you don’t need me to tell you, but if you ever experience any of the above side effects when using lash serum, you should discontinue using it right away and consult a doctor.

2- Dryness

Because of a lack of moisture in the skin around the eye, you can experience dryness or flakiness of the skin.

3- Swelling of the Eyelids

You may feel your eyelids getting puffy or enlarged. You may react to an ingredient in the serum or have an allergic reaction.

4- Changes in Eye Color

Eye color is determined by the amount of melanin (the pigment that gives color to your eyes). Because prostaglandins can increase melanin production, it may cause increased pigmentation in the iris.

What’s interesting is that blue eyes don’t have much melanin to start with (as opposed to brown eyes), so they’re in theory less affected by this problem.

5- Darkening of the Skin Around the Eyes (Hyperpigmentation)

If your lash serum uses chemicals known as prostaglandin analogs, you might notice some skin darkening around the eye area. This is known as hyperpigmentation and can occur if the lash serum formula touches certain parts of the eyelid.

Since melanin is responsible for giving our skin its color, overproduction can lead to hyperpigmentation or darkening of the skin.

6- Orbital Fat Loss

Another side effect you might notice when using lash serums is fat loss around the eyes. This is probably one of the most serious side effects of an eyelash growth serum, as it isn’t reversible.

So, how can a lash serum cause orbital fat loss?

Put simply, fat loss around the eyes (known as orbital fat loss) can occur when the prostaglandin analogs come into contact with the delicate eye area. These compounds can cause a shrinking of fat around the eyes, leading to an overall more sunken appearance.

Who’s More at Risk?

Some people might be more susceptible than others to have an adverse reaction. This is not an exhaustive list and I always recommend you read the label carefully and speak to your doctor if in doubt.

• Individuals with sensitive skin or allergies: Lash serums that contain active ingredients can trigger an allergic reaction for some and compound your sensitivities.
• Contact lens wearers: Irritation can be exacerbated by contact lens use.
• People who have undergone chemotherapy or radiation therapy: The immune system is weakened by these treatments and can make the body more susceptible to an adverse reaction.
• Underaged individuals: Latisse the only FDA-approved lash serum is not approved for people under the age of 18.
• Pregnant or breastfeeding women: The safety of lash serums has not been extensively studied in pregnant or breastfeeding women. As such, it’s advisable to stay on the safe side of things and wait until your pregnancy is over.

How To Mitigate Risks

Fortunately, there are a few things you can do to reduce the risk (not eliminate them) of having side effects.

• Patch test: This is the most straightforward way to see if your body reacts to any ingredients in a particular growth serum. Simply apply a small amount of the product on your wrist and wait 24 hours. If you’re sensitive or allergic, you may experience swelling, redness, or irritation. Don’t use the product if that’s the case.
• Consult with your doctor: That seems like an obvious thing to say, but your doctor can help with your medical history and regular follow-ups to spot adverse reactions.
• Use as directed: Never exceed the recommended dosage. Most lash serums require one single daily application. Using too much product can increase your chances of having side effects.
• Get a prostaglandin-free serum: The industry is evolving and many quality growth serums that don’t have any prostaglandin have emerged. I’ve started to compile a full list of prostaglandin-free serums here.

Lash Serum Alternatives

My two favorite alternatives that are 100% natural and safe are coconut oil and castor oil. Granted, you might not have an eyelash explosion, but sometimes it’s better to be safe than sorry.

Coconut Oil

Did you know that coconut oil is a natural moisturizer? In fact, it’s widely used in the beauty industry for its numerous benefits.

For instance, coconut oil contains high levels of lauric acid which can penetrate the hair shaft for a deep moisturizing effect. It can also prevent hair damage by nourishing the hair follicle.³

To get started safely, warm up the oil and simply apply some to your lash line a few times per week. Leave it one for 30 minutes before washing it off. With consistent use, you may notice stronger and thicker lashes.

Castor Oil

I love castor oil. It’s a versatile oil that contains ricinoleic acid that promotes hair growth in studies. Additionally, it’s full of omega-6 and omega-9 fatty acids which nourish and moisturize the hair follicle. This helps prevent breakage and split ends.

What’s so great about this oil is that it’s easily accessible. You can get it for cheap in most health food stores or groceries.

FAQs

References

1. Mayo Clinic (2003). Bimatoprost (Intraocular Route, Ophthalmic Route). Retrieved from https://www.mayoclinic.org/drugs-supplements/bimatoprost-intraocular-route-ophthalmic-route/description/drg-20062270 (Accessed on July 6th, 2022).
2. Doll T, Schwartz S, Hom M, O’Dell, Kwan J, Periman LM, et al. Over-the counter eyelash growth serum use: Self-reported pervasiveness and user satisfaction. Presented at: The Association for Research in Vision and Ophthalmology; 2020. Virtual meeting.
3. Aarti S. Rele, R.B. Mohile. (2003) Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage. Retrieved from https://pubmed.ncbi.nlm.nih.gov/12715094/ (Accessed on July 6th, 2022).