Health condition
Pseudoporphyria
Pseudoporphyria looks exactly like porphyria cutanea tarda - fragile, blistering skin on the backs of the hands - but porphyrin tests are normal; the usual culprits are medicines such as naproxen, diuretics, or the combination of dialysis and UVA exposure.
Why trust this guide
- 01
Editorial team
Written by our editorial team from the UK sources listed on each page.
- 02
Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
- 03
Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
The symptoms to recognise, when to seek help, which specialist to see, and what treatment usually involves.
-
Skin fragility, tense blisters and scarring on sun-exposed hands and face, indistinguishable clinically from porphyria cutanea tarda
-
Blood, urine and stool porphyrin levels are normal - the defining feature
-
Recognised triggers: NSAIDs (especially naproxen), frusemide, nalidixic acid, voriconazole, sunbeds and chronic kidney disease with dialysis
-
Management is trigger withdrawal and photoprotection; blisters heal over weeks once the cause is removed
Understanding the condition
What it is and what happens next.
What causes it, how it is diagnosed, and the treatment routes available in the UK.
What it is and how it feels
Pseudoporphyria matters chiefly because of what it mimics: a person develops the classic fragile, blistering sun-exposed skin of PCT, but the metabolic machinery of haem synthesis is intact. Naproxen-induced cases are well documented in children and adults, and in people on haemodialysis the condition can appear without any drug trigger at all.
Diagnosis and treatment routes
The workup is therefore a full porphyrin screen to exclude true porphyria, a structured medication review reaching back several months, and enquiry about sunbed use. Stopping the offending agent (with an alternative anti-inflammatory chosen where needed), strict UVA-inclusive photoprotection and simple wound care for blisters usually resolve the condition, although skin fragility can lag for months. In much of the UK, a routine NHS referral to the relevant specialist clinic can take several months, whereas an initial appointment with a private consultant is typically available 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 consultant dermatologist. 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 of the emergency symptoms described above.
Frequently asked
Common questions about Pseudoporphyria.
Quick, plain-English answers to what people ask us most.
-
What is pseudoporphyria?
Pseudoporphyria is a skin condition causing blistering and fragility resembling porphyria cutanea tarda, but without the abnormal porphyrin levels found in true porphyria, often related to certain medications or dialysis.
-
What causes pseudoporphyria?
It's commonly linked to certain medications, particularly some antibiotics, diuretics, and non-steroidal anti-inflammatory drugs, as well as being associated with long-term kidney dialysis, with sun exposure often playing a triggering role.
-
What are the symptoms?
Skin fragility and blistering, particularly on sun-exposed areas such as the hands and forearms, closely resembling the appearance of true porphyria cutanea tarda.
-
Is pseudoporphyria dangerous?
No, it's not dangerous to overall health, though it can cause troublesome skin symptoms, and it's important to distinguish it from true porphyria, which has different implications and management.
-
Can pseudoporphyria be treated?
Yes, treatment involves identifying and, where possible, stopping the causative medication, alongside strict sun protection, with symptoms typically improving once the trigger is removed.
-
How is pseudoporphyria diagnosed?
Diagnosis involves the characteristic skin appearance, a review of current medications, and specific porphyrin blood and urine tests, which are normal in pseudoporphyria, unlike in true porphyria.
-
How long does pseudoporphyria take to resolve?
Symptoms typically improve within weeks to a few months of stopping the causative medication and maintaining good sun protection, though this can vary depending on the specific trigger.
-
Pseudoporphyria vs porphyria cutanea tarda — what's the difference?
The two look very similar on the skin, but porphyria cutanea tarda involves genuinely abnormal porphyrin levels detectable on specific testing, while pseudoporphyria has normal porphyrin levels; this distinction is important as management differs.
-
Can pseudoporphyria be prevented?
Being aware of medications known to be associated with this condition and using good sun protection while taking such medications can help reduce the risk of developing pseudoporphyria.
-
When should I see a dermatologist, and how quickly can I be seen privately?
See a dermatologist for unexplained skin fragility and blistering, particularly if taking relevant medications or on dialysis. Private dermatology assessment is typically available within about two weeks, faster than standard NHS waiting times.