Project Peach
Pharmacy Group Wales Logo
We use cookies to enhance your browsing experience. By clicking 'I Understand and Accept', you consent to our use of cookies.
I understand and accept
No, I don't want to use cookies
My Account
Control Panel
An example toast message
Do Something
Login
en
en
Pharmacy Group Wales LogoPharmacy Group Wales Logo
en
en
Change Language
Login
My Account
Control Panel
Order Prescription
Book Appointment
Services
Pharmacies
Health & Advice
Log Out
Order Prescription
Book Appointment
Login
Login
en
en
Do Something
Login
en
en
Pharmacy Group Wales LogoPharmacy Group Wales Logo
en
en
Change Language
Login
My Account
Control Panel
Order Prescription
Book Appointment
Services
Pharmacies
Health & Advice
Log Out
Order Prescription
Book Appointment
Login
Login
en
en
Acanthosis nigricans
Symptoms of acanthosis nigricans

The main symptom of acanthosis nigricans is patches of skin that are darker and thicker than usual.

They can appear anywhere on the body.

A dark patch of skin on the armpit of a person with white skin. The patch covers most of the person's armpit.

They're most common in skin folds, such as the armpits, neck or groin.

Dark patches of skin covering the armpit of someone with medium brown skin. There are also about 50 small skin tags.

Some people also have tiny growths (skin tags) on the patches.

The patches often appear gradually without any other symptoms.

Sometimes the skin may be itchy.

See a GP if:

  • you have new dark patches on your skin
  • you have any skin changes you're unsure about
What happens at your appointment

A GP can usually tell if it's acanthosis nigricans by looking at your skin.

Although acanthosis nigricans is usually harmless, it's best to get any skin changes checked out.

Rarely, it can be a sign of something more serious, such as cancer.

You may need some tests to find out what's causing the patches.

Causes of acanthosis nigricans

The most common cause of acanthosis nigricans is obesity.

Other causes include:

Sometimes healthy people with no other conditions get acanthosis nigricans. This is more common in people with black or brown skin.

Treating acanthosis nigricans

Once a GP knows what's causing acanthosis nigricans, they can recommend the best treatment.

The patches should fade over time once the cause is treated.

If you're very overweight, a GP may recommend losing weight.

Depending on the cause, they may also recommend:

  • medicine to balance your hormones
  • medicine to balance your insulin levels
  • changing your medicine to one that does not cause the patches

There's no specific treatment for the patches themselves. A skin specialist (dermatologist) may be able to suggest treatments to improve their appearance, but finding and treating the cause is usually recommended first.

Last Reviewed
25 June 2025
NHS websiteNHS website
Pharmacy Group Wales Logo
We take pride in providing the community with exceptional community pharmacy services and tailored care. Our priority is your health and well-being.
Menu
About Us
Patient Account Deletion Request
Pharmacy Services
Order Prescriptions
Health A-Z
Healthy Living Zone
Download Our App
Our Stores
Store Locator
Penlan Pharmacy - Collection Only
Script Direct - Delivery Only
No stores found
Pharmacy Group Wales © 2025
Website by bewell.uk
Privacy Policy
Cookies Policy
Terms & Conditions