Where acne occurs can be revealing about what’s causing it. This is called acne mapping. If you find that your acne breakouts are consistently only on one side of your face, that narrows down its possible causes. It also makes it easier to figure out how to prevent it. 

Let’s investigate. Here are five possible causes of acne occurring only on one side of your face. 

1. Your Pillow 

By far the most common cause of one sided face acne is the pillow. As we explained in a previous article on pillow hygiene, your pillow and pillowcase can ruin your skin. 

Your pillow quickly accumulates with dead skin cells, oils, skin products, dirt, allergens like dust mites, bacteria and other kinds of gunk. These transfer onto your skin every time you are in bed, and can lead to acne outbreaks as your pores get clogged.

If you sleep mostly with one side of your face on the pillow, you’ll notice that you get breakouts only on that side. 

What to Do About It 

Change your pillowcase once or twice a week. If you have sensitive skin or sweat a lot at night, do it every other day. 

You can also try changing your sleeping positions throughout the night to avoid exposing one side of your face to the pillow for too long. 

You may also want to switch to a silk or bamboo pillowcase. Traditional cotton pillowcases absorb a lot of moisture and oil from your face, leaving your skin dry and increasing the risk of a breakout. 

Beauty pillowcases, especially those made from silk, protect your skin by reducing moisture absorption and having a smoother texture that causes less friction (friction can also cause acne, as well as skin aging).   

An antibacterial pillowcase like the Jax Sheets pillowcase can also help. It keeps bacteria off the pillow, which reduces the risk of acne, especially painful cystic acne. 

2. Your Usually Touch That Side of Your Face 

Do you often, probably unconsciously, touch one side of your face with your hands? Or maybe you like to support your head on your palm. 

Your hand touches a lot of surfaces and can transfer dirt, oils and bacteria onto your sensitive face. Do it often enough and you’ll probably notice breakouts on the side of your face that you touch most. 

What to Do About It? 

Train yourself to avoid touching your face. If it is an unconscious tic, find something else to replace it. If you often hold your head in your hand, practice sitting upright. 

As you retrain your muscle memory, try to keep your hands clean since you will undoubtedly touch your face now and then. Wash your hands with soap and water often and carry a bottle of sanitizer with you.

Be careful when in public areas. Avoid touching surfaces such as walls, escalator/stair railing and poles.    

3. Your Phone 

If the acne breakout is on the side of your face that you hold your phone against and located on the upper part of your jaw and cheek, then your phone might be the culprit. 

Your smartphone is even dirtier than your hands. Not only do you smudge it with sweat, oils and bits of food, your phone also comes into contact with different kinds of unhygienic surfaces. 

Everytime you make a call and hold the phone against your ear, you are clogging your pores with whatever gunk is on your screen. 

What to do About It

Switch to taking calls on loudspeaker or wireless headphones/earbuds. This ensures your phone never comes into contact with your face. 

If you still need to occasionally hold your phone against your ear, apply some isopropyl alcohol to a lint-free cloth and wipe down the phone. 

4. Your Hair 

If you have a hairstyle that brings hair down to one side of the face, it can lead to an acne breakout on that side of the face. 

Hair can trap dirt and sweat on the skin, causing a breakout. Hair products can also clog pores on your face.

What to do About It

Avoid hair styles that bring hair into contact with your face, especially if you have sensitive skin. But if you have to get such a style, you’ll need to cleanse your face at least twice a day to prevent clogging. 

Also be careful which hair products you are using. Look for products that are less likely to cause acne on your skin.   

5. Hormones  

Hormonal acne can sometimes be unpredictable. In many people, hormonal acne occurs on the lower part of the face — the jawline, cheeks and chin. 

But it can also occur on your neck, back, chest and other parts of your face. A lot of women have reported getting hormonal acne only on one side of your face. 

If the breakout coincides with a major hormonal event like ovulation, menstruation, pregnancy or menopause, then it is likely hormonal even if it is only on one side.

What to do About It

Even if the acne is hormonal, an unhygienic pillow or touching your face can make it more likely to appear on one side of the face. So even as you seek treatment for the breakout, follow the recommendations we have discussed above. It can help reduce the intensity of the breakout.