by Scholten A
( Nevus flammeus )


A port-wine stain is a reddish-purple mark on the skin. It is usually present at birth. It does not go away on its own. However, it can be treated.


Port wine stains are caused by a problem with small blood vessels in the skin. Blood vessels normally open and close. In this condition, the blood vessels stay open. Blood fills the vessels. This causes a purple color and raised skin.

Risk Factors

There are no known risk factors for this condition.

Port wine stains are more common in people who have:

  • Sturge-Weber syndrome
  • Klippel-Trenaunay-Weber syndrome

These are conditions that affect the blood vessels.


The marks vary in size. They are usually on the head, neck, arms, and legs. Their appearance may change:

  • In children—they are flat, red, or light purple.
  • In adults—they are raised and purplish, getting darker and thicker over time.

They may bleed when scratched.

Marks near the eyes may cause eye problems.


The doctor will ask about your symptoms and health history. A physical exam may be done. Port wine stains can be diagnosed based on how they look. If the doctor has any concerns, a biopsy may be taken. If the eye is involved, an eye exam may be done. You may also need to see a doctor who treats skin problems.

Skin Biopsy
Skin proceedure
Copyright © Nucleus Medical Media, Inc.


Port wine stains are often harmless. Moisturizing can help if the skin gets dry.

Treatment may be needed if a person does not like the way a mark looks. Options are:


Laser treatment can destroy the blood vessels causing the mark. Risks may be scarring and skin lightening or darkening.

Flash-lamp pumped pulse dye laser may be used. It may involve multiple treatments.

Other Treatments

Less common treatments are freezing, surgery, and radiation to the blood vessels.


There are no known guidelines to prevent port wine stains.


American Academy of Dermatology 

Vascular Birthmarks Foundation 


Canadian Dermatology Association 

Health Canada  


Port wine stain. Nemours Kids Health website. Available at: Accessed February 8, 2021.

Port-wine stain information. Vascular Birthmark Foundation website. Available at: Accessed February 8, 2021.

Sturge-Weber Syndrome. EBSCO DynaMed website. Available at: Accessed February 8, 2021.

Zallmann M, Leventer RJ, et al. Screening for sturge-weber syndrome: a state-of-the-art review. Pediatr Dermatol. 2018;35(1):30-42.

Revision Information