Health condition
Porphyria
The porphyrias are a group of inherited disorders of haem production, dividing broadly into acute forms that cause attacks of severe abdominal pain and neurological symptoms, and cutaneous forms that cause skin fragility or painful light sensitivity.
Why trust this guide
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Editorial team
Written by our editorial team from the UK sources listed on each page.
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Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
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Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
Which gene and test confirm it, who should be tested in the family, and which specialist to see.
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Eight main types; the acute porphyrias (AIP, VP, HCP) cause attacks, the cutaneous forms (PCT, EPP) cause skin disease
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Acute attacks: severe abdominal pain, vomiting, hyponatraemia, dark or reddish urine, agitation - often triggered by drugs, hormones, fasting or alcohol
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First-line tests differ by presentation: urinary PBG for suspected acute attacks; plasma or blood porphyrins for skin disease
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The UK National Acute Porphyria Service and specialist labs coordinate diagnosis, drug safety advice and family testing
Understanding the condition
What it is and what happens next.
What causes it, how it is confirmed, and the testing and specialist routes available in the UK.
What it is and how it presents
Haem is built along an eight-step assembly line, and each porphyria corresponds to a bottleneck at one step, with the intermediates that pile up determining the symptoms. Neurotoxic precursors cause the acute attacks that famously mimic surgical abdomens and psychiatric crises; light-reactive porphyrins deposited in skin cause blistering fragility or immediate burning pain in sunlight. Because both pictures are rare and episodic, diagnostic delays of many years remain the norm.
Testing, surveillance and specialist care
The key is requesting the right sample at the right moment - a protected, promptly analysed urine for porphobilinogen during a suspected attack, or plasma porphyrin scanning for skin presentations - after which enzyme and genetic testing type the porphyria precisely and unlock family cascade testing, safe-drug lists and access to specialist services. NHS clinical genetics services carry some of the longest waits in the health service, often many months for a first appointment, whereas private genetic testing and a specialist review can typically be arranged within around two weeks.
Seeing a specialist
Who to see, and how quickly you can be seen.
The specialist for this condition is usually a specialist porphyria service physician. Your GP can refer you on the NHS, or you can arrange a private consultation directly.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any emergency symptoms.
Frequently asked
Common questions about Porphyria.
Quick, plain-English answers to what people ask us most.
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What is porphyria?
Porphyria is a group of rare disorders affecting the production of haem, an essential component of haemoglobin, which can cause a variety of symptoms depending on the specific type, ranging from skin problems to acute abdominal and neurological attacks.
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What causes porphyria?
Most types are caused by inherited deficiencies in specific enzymes involved in the haem production pathway, with symptoms often triggered or worsened by certain medications, alcohol, hormonal changes, fasting, or infections.
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What are the symptoms of porphyria?
Symptoms vary considerably depending on the type: acute porphyrias cause severe abdominal pain, neurological symptoms, and psychiatric changes during attacks, while cutaneous porphyrias cause skin fragility and sun sensitivity.
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Is porphyria dangerous?
Acute porphyria attacks can be serious and, in severe cases, life-threatening if not promptly recognised and treated, while cutaneous forms are generally less dangerous but can significantly affect skin health and quality of life.
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Is porphyria hereditary?
Most forms of porphyria are inherited genetic conditions, though the specific inheritance pattern and the presence of symptoms (which often depend on additional triggers) vary between the different types.
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Can porphyria be treated?
Yes, treatment depends on the specific type, ranging from avoiding known triggers and specific medication during acute attacks, to venesection or other treatments for cutaneous forms; newer targeted treatments are also available for some acute porphyrias.
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How is porphyria diagnosed?
Specific blood, urine, and stool tests measuring porphyrins and related compounds, along with genetic testing to confirm the specific type, establish the diagnosis, often requiring specialist laboratory input.
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How long do porphyria attacks last?
Acute attacks can last several days to weeks, particularly if a trigger isn't identified and removed promptly, while symptoms of cutaneous porphyrias tend to be more persistent unless specific treatment is given.
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Acute vs cutaneous porphyria — what's the difference?
Acute porphyrias cause episodic attacks of severe abdominal pain and neurological symptoms, while cutaneous porphyrias primarily cause skin fragility and sun sensitivity without the same acute attack pattern; specific testing identifies which type or types are involved.
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When should I see a specialist, and how quickly can I be seen privately?
See a specialist promptly for unexplained severe abdominal pain with neurological symptoms, or persistent skin fragility and sun sensitivity. Private specialist assessment is typically available within about two weeks, faster than standard NHS pathways for this rare condition group.