Overview
Actinic prurigo (sometimes called hereditary polymorphic light eruption or Hutchinson's summer prurigo) is a rare skin condition in which exposure to sunlight triggers an intense itchy rash. It is considered a type of photodermatosis, meaning it is a disease caused by abnormal sensitivity to ultraviolet (UV) light. The condition most commonly begins in childhood and can persist for years or even a lifetime. People with actinic prurigo develop itchy bumps (papules), small blisters, and thickened or scarred patches on sun-exposed areas of the skin, including the face, neck, arms, and hands. The lips are frequently affected, leading to a condition called cheilitis — cracked, swollen, and crusted lips. In some cases, the eyes can also be involved, causing redness and irritation of the conjunctiva. The itching can be severe and significantly affect quality of life. The exact cause is not fully understood, but there is a strong genetic component. Actinic prurigo is closely associated with certain HLA (human leukocyte antigen) types, particularly HLA-DR4 and its subtype DRB1*0407. Treatment focuses on sun protection, topical corticosteroids, and in more severe cases, thalidomide, which has shown significant effectiveness. Other options include antimalarials, phototherapy (controlled UV exposure to build tolerance), and immunosuppressive medications. While there is no cure, many patients can manage their symptoms effectively with proper treatment and sun avoidance strategies.
Also known as:
Key symptoms:
Intense itching on sun-exposed skinRed bumps and small blisters on the face, arms, and handsThickened, rough skin patches from repeated scratchingCracked, swollen, and crusted lips (cheilitis)Scarring on the face and armsEye redness and irritationSkin rash that worsens with sun exposureOozing or crusting of skin lesionsDark marks or discoloration left after rash healsRash that may persist even in winter months in severe casesExcoriations from scratching
Multifactorial
Caused by a mix of several genes and environmental factors
Childhood
Begins in childhood, roughly ages 1 to 12
FDA & Trial Timeline
1 eventChulalongkorn University
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Actinic prurigo.
1 clinical trialare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Actinic prurigo.
Community
No community posts yet. Be the first to share your experience with Actinic prurigo.
Start the conversation →Latest news about Actinic prurigo
Disease timeline:
New recruiting trial: Multi-centred Clinico-genetic Study of Actinic Prurigo in Thailand
A new clinical trial is recruiting patients for Actinic prurigo
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Is my condition definitely actinic prurigo, or could it be another type of sun sensitivity?,Should I have HLA typing to help confirm the diagnosis?,What is the best sun protection strategy for my specific situation?,Is thalidomide appropriate for me, and what are the risks and monitoring requirements?,Are there safer alternatives to thalidomide that might work for my level of severity?,Should I see an eye doctor to check for eye involvement?,Will my symptoms improve as I get older, or is this likely to be lifelong?
Common questions about Actinic prurigo
What is Actinic prurigo?
Actinic prurigo (sometimes called hereditary polymorphic light eruption or Hutchinson's summer prurigo) is a rare skin condition in which exposure to sunlight triggers an intense itchy rash. It is considered a type of photodermatosis, meaning it is a disease caused by abnormal sensitivity to ultraviolet (UV) light. The condition most commonly begins in childhood and can persist for years or even a lifetime. People with actinic prurigo develop itchy bumps (papules), small blisters, and thickened or scarred patches on sun-exposed areas of the skin, including the face, neck, arms, and hands. The
How is Actinic prurigo inherited?
Actinic prurigo follows a multifactorial inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Actinic prurigo typically begin?
Typical onset of Actinic prurigo is childhood. Age of onset can vary across affected individuals.
Are there clinical trials for Actinic prurigo?
Yes — 1 recruiting clinical trial is currently listed for Actinic prurigo on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Actinic prurigo?
15 specialists and care centers treating Actinic prurigo are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.