Research Library
Erythropoietic Protoporphyria (EPP)
Symptoms, Treatment and Everyday Life
Erythropoietic protoporphyria, known by the English abbreviation EPP, is a rare inherited condition that can make exposure to light intensely painful. Symptoms usually begin in childhood. A person can experience severe pain even when their skin looks almost the same as usual. GeneReviews
Living with EPP can turn everyday activities into difficult decisions: where to sit, how to get to work, whether to join an outing and how to explain the pain to someone else. Understanding the condition can help you ask better questions, plan around your needs and find support.
Need help finding medical care? The United Porphyrias Association’s patient navigator helps people find specialists and resolve questions about testing and access to treatment.
What causes EPP?
Your body produces a substance called heme, which helps the blood carry oxygen. Producing heme requires several steps.
In EPP, an inherited change makes the final step work less effectively. As a result, a substance the body normally uses to produce heme builds up. That substance is called protoporphyrin. When it absorbs certain kinds of light, it can damage nearby tissues and cause pain. European Porphyria Network
EPP belongs to a group of conditions called porphyrias. They affect how the body produces heme, but they do not all cause the same problems.
A related condition called X-linked protoporphyria, or XLP, can cause similar reactions to light but has a different inherited cause. Knowing which condition a person has helps guide their care and testing for relatives. A genetics specialist can explain what the results mean for relatives or future children. UPA: Erythropoietic protoporphyria and XLP
EPP symptoms and diagnosis
Exposure to light may first cause tingling, itching or burning. Severe pain can follow. The skin may become red or swollen, although some people have few visible changes. Pain can continue for hours or days after exposure ends. GeneReviews
The appearance of the skin does not reliably show how much pain a person is feeling. Research on EPP symptoms found that few or no visible skin changes do not rule out the condition or mean its effects are mild. Study of light-related EPP symptoms
Other conditions can also cause sensitivity to light, so symptoms alone do not confirm EPP.
What test is used to detect EPP?
A blood test measures how much protoporphyrin has accumulated in red blood cells. Its medical name is total erythrocyte protoporphyrin. “Erythrocyte” simply means red blood cell.
The laboratory also measures the different forms of protoporphyrin because the proportions between them help identify the condition. An ordinary urine test for porphyria alone does not rule out EPP. American Porphyria Foundation
A medical professional familiar with porphyrias can order the appropriate tests and explain the results. Tests for inherited changes may then help establish the cause and determine whether relatives should be assessed. Summary of consensus recommendations
Preparing for an appointment
Bring a brief summary of:
- When the symptoms started and what they feel like.
- Where they occur, such as outdoors, in a car or under indoor lighting.
- How long they last and how they affect sleep, school, work or daily activities.
- Previous test results, the medicines and supplements you take, and any similar problems in the family.
Photographs can help if visible changes occur. If they do not, a written description is still useful. You do not need to expose yourself deliberately to light to prove that something is wrong.
Useful questions include: “Could these symptoms fit EPP?”, “Did my previous tests assess that possibility?” and “Should I see a porphyria specialist?”
What triggers EPP symptoms?
The inherited condition makes a person sensitive to light. Exposure to light triggers the reaction.
Visible light is the light we can see. It includes the colors of the rainbow. The blue-violet part is particularly important in EPP. Sunlight passing through an ordinary window can also cause symptoms. GeneReviews
Some people also report problems with artificial lighting. Sensitivity varies, so another person’s experience cannot tell you how much exposure you can tolerate. Interview study involving people with EPP
Tell your medical team which places and situations cause difficulties. Advice about “porphyria triggers” may refer to a different type of porphyria, so check that it applies to EPP.
Living with EPP: protection and everyday activities
Why might sunscreen be insufficient?
A sunscreen’s SPF number describes protection against the ultraviolet rays that cause sunburn. Ultraviolet, or UV, light is invisible. Visible light is also involved in EPP, so a high SPF alone does not tell you whether a product will prevent a reaction.
Some tinted sunscreens or thick preparations that block light may offer additional protection. Their benefit is limited, and they should not be used as a reason to extend exposure. Clothing and avoiding light that causes symptoms remain important. UPA guidance on protection from light
Ask a medical professional with EPP experience about clothing, curtains or protective window films, and changes to lighting. A label saying “UV protection” does not, by itself, establish that a product provides suitable protection for EPP.
Making school, work and outings easier
Start with the situations that cause the most difficulty. An indoor alternative, a seat away from a bright window or a journey with less time outdoors may help. Ask the person with EPP what works for them; shade or a cloudy sky may not be enough.
At school, discuss classrooms, outdoor activities, transport and what staff should do when symptoms appear. In the United States, families can ask about a written school support plan that records the adjustments a child needs. UPA’s school-support resource shares a young person’s experience and questions to raise with the school.
At work, useful changes may include lighting, desk location, travel or schedules. The aim is to make participation easier while respecting the person’s needs.
A plan for pain and medical follow-up
Ask the professional treating you for a clear plan: what to do when symptoms start, how to manage a painful episode and when to seek medical help. It is easier to agree on that plan before you are going through a difficult moment.
Care also includes checking for problems beyond the skin. EPP can affect the liver. The medical team may also check iron and vitamin D levels. Ask before starting supplements, because iron recommendations differ between EPP and XLP. UPA information on medical care
EPP treatment: what is approved and what is being studied?
Scenesse and afamelanotide
In the United States, Scenesse is an FDA-approved prescription medicine for adults with EPP who have had painful reactions to light. Its purpose is to increase the time they can spend exposed to light without pain.
Scenesse contains a medicine called afamelanotide. It comes as a small implant that a trained healthcare professional places under the skin.
Protection from light is still necessary during treatment. Risks include serious allergic reactions and changes in skin color. Regular skin examinations are recommended. Its safety and effectiveness in children have not been established. Scenesse prescribing information
Ask the specialist what benefit would be reasonable to expect, what follow-up checks are needed and where treatment is available. Costs and insurance coverage also need to be checked for your situation.
You may also find afamelanotide under the name Melanotan 1. Our explanation of Melanotan 1 and afamelanotide clarifies those names and their relationship to Scenesse.
A research vial or another product marketed as Melanotan 1 does not replace the approved Scenesse implant. Sharing a name or claiming to contain the same substance does not make the finished products equivalent.
Treatments still being studied
Other medicines are being investigated. As of October 4, 2026, the United Porphyrias Association reports a US expanded-access program for bitopertin, a medicine still being studied for EPP and XLP.
“Expanded access” means that some people who meet the requirements may be assessed to receive an investigational medicine outside a clinical trial. It does not mean that the medicine is FDA approved or that everyone can receive it. Current information about the bitopertin program
A specialist or patient navigator can help you understand the current options. For children, ask specifically about care and research opportunities suitable for their age.
How family members can help
Believe what the person tells you about their pain, even when their skin looks the same as usual. Ask what support they need, and listen when they say they must move away from the light or change a plan.
Keep inviting them. Suggest an indoor gathering or another time and place. Let them take part in deciding what they can manage, and reassure them that they can change their mind if symptoms appear.
For a child, give teachers, relatives and activity leaders a simple explanation and an agreed plan for responding to symptoms. As the child grows, help them practice explaining what they need.
EPP can also affect emotional wellbeing. Published interviews describe effects on social life, daily activities and work. Talking with someone who understands EPP, or seeking mental-health support when emotional distress becomes difficult to manage, may help. Research based on patient interviews
Where to find EPP support and reliable resources
| If you need… | A useful starting point |
|---|---|
| Help finding a specialist or understanding testing and access to treatment | United Porphyrias Association’s patient navigator |
| Information about the condition and its care | UPA’s EPP and XLP resource |
| Family activities, community and practical support | Shadow Jumpers, which supports families affected by EPP and other conditions that cause sensitivity to light |
| Resources for children and parents | American Porphyria Foundation’s Shadow Jumpers resources |
| Dutch-language information and community in the Netherlands | EPP Patient Association |
Available programs and their requirements vary. Check each organization’s current information, including the countries or regions where it offers support.
Watch: everyday life with EPP
The Rarely Discussed interview about living with EPP includes personal experiences of childhood, social activities and the adjustments needed to work with light sensitivity.
These passages may help start a family conversation:
The interview describes one person’s experience. Check medical comments and older statements about treatment availability against current information from your medical team.
Sources and further reading
- GeneReviews: Erythropoietic protoporphyria.
- Evidence-based recommendations for diagnosis and management.
- Scenesse prescribing information.
- Research on symptoms and effects on everyday life.
Educational Notice: This information can help you understand EPP and prepare for conversations with healthcare professionals. It cannot confirm a diagnosis or determine which treatment is right for you. Products intended for research do not replace prescribed medical care.
Author: TaylorTides
Medical review status: Not reviewed by a licensed clinician
Research reviewed: October 4, 2026
You do not have to resolve every difficulty at once. Finding medical care with experience in the condition, preparing a few questions or making it easier to join a family activity can be a useful next step when living with erythropoietic protoporphyria.