Acute porphyrias are rare conditions that affect how the body makes haem - a substance that makes blood look red and helps blood carry oxygen around the body.
Acute porphyrias are called ‘acute’ because they cause attacks that come on suddenly and last a short time.
Most types of porphyria are inherited from 1 or both parents, and are caused by a mutation in a gene that makes haem. Haem, also known as ‘heme’, is part of a protein called haemoglobin, which is found in red blood cells.
There are 4 types of acute porphyrias:
- acute intermittent porphyria (AIP) - the most common type. Symptoms develop more commonly in women
- variegate porphyria (VP)
- hereditary coproporphyria (HCP)
- delta-aminolevulinic acid dehydratase porphyria (ALAD) - the rarest type
Acute porphyrias can cause potentially life-threatening episodes or attacks. See your doctor or go to a hospital if you have, or think you may have, an acute porphyria.
What are the symptoms of acute porphyrias?
It is thought that most people who have the gene mutations that cause acute porphyrias will never have an acute attack. However, a small number have repeated attacks, but are healthy between these attacks.
The frequency and severity of attacks differ from person to person.
The symptoms of all types of acute porphyria include:
- constipation, tiredness, irritability and insomnia just before an attack
- tummy pain
- red pee
- seizures, muscle weakness, paralysis
- a fast heart beat
- back and leg pain
- difficulty breathing
If you have variegate porphyria or hereditary coproporphyria, you may develop skin changes, such as blisters, especially on skin that has been exposed to the sun.
What cause acute porphyria attacks?
While most acute porphyrias are caused by a gene mutation that is passed on in families, attacks can be triggered by different factors, including:
- certain medications - such as some antibiotics, the contraceptive pill and medicines that prevent seizures (fits)
- hormonal changes in women
- female gender
- low-calorie diets
How are acute porphyrias diagnosed?
Acute porphyrias are usually diagnosed with a urine test. You may need more urine tests as well as stool and blood tests to identify the type of porphyria you have.
If you are diagnosed with an acute porphyria, other members of your family should also be tested as most porphyrias are inherited.
Treatment for acute porphyrias
Treatment is the same for all types of acute porphyria.
As attacks are often triggered by specific factors, you may be able to reduce the chance of an episode by avoiding possible triggers, such as:
- drinking too much alcohol
- recreational drug use
- skipping meals
- contraceptive pills - speak to your doctor about other forms of contraception you can use
If you have an acute porphyria attack, you will usually need to be treated in hospital.
Treatment may include:
- removing exposure to potential triggers, such as certain medicines
- close observation and fluids given through a vein in the arm (IV)
- for mild attacks, eating and drinking glucose-containing drinks and high-energy (carbohydrate-rich) foods
- IV glucose (sugar)
- IV haem arginate - a medicine to reduce the build up of substances, called porphyrins, that cause the attack
It can take 3 to 4 days for your symptoms to fully resolve after treatment with haem arginate.
If you have repeated or severe acute porphyria attacks that do not respond to treatment, your doctor or specialist may recommend a liver transplant.
This is because when you have acute porphyria, your liver may not make certain enzymes (proteins used for chemical reactions in the body) that it should.
This can cause porphyrins to build up in your body and lead to attacks. Replacing your liver with one that produces these missing enzymes can help prevent future attacks.
When will I be able to return to normal?
Most people recover fully from an acute porphyria attack.
You can help prevent further attacks by avoiding the things that trigger an attack, as much as possible.
If you suspect that a specific medication you are taking has triggered an attack, speak to your doctor. They will usually be able to tell you if it is safe to stop taking that medication and give you advice on alternative treatments.
It is likely that your doctor will give you a card or medic alert bracelet that confirms you have an acute porphyria and the precautions you need to take. Carry this card with you or wear the bracelet at all times.
Where to find further help
Speak to your doctor or specialist for specific advice on acute porphyrias. You can also get further information or support from organisations, such as the American Porphyria Foundation and the European Porphyria Network.
If you are worried that you may have acute porphyria, check your symptoms by downloading our free Self-Assessment Tool.
Date of last review: 16 June 2020
Acute Porphyrias - Endocrine and Metabolic Disorders - MSD Manual Professional Edition [Internet]. MSD Manual Professional Edition. 2020 [cited 25 February 2020]. Available here.
Excellence N. Acute porphyrias | Treatment summary | BNF content published by NICE [Internet]. Bnf.nice.org.uk. 2020 [cited 25 February 2020]. Available here.
Red blood cell count [Internet]. nhs.uk. 2020 [cited 26 February 2020]. Available here.
Acute intermittent porphyria - Symptoms, diagnosis and treatment | BMJ Best Practice [Internet]. Bestpractice.bmj.com. 2020 [cited 26 February 2020]. Available here.
Variegate porphyria [Internet]. Uptodate.com. 2020 [cited 26 February 2020]. Available here.
Hereditary coproporphyria [Internet]. Uptodate.com. 2020 [cited 26 February 2020]. Available here.
ALA dehydratase porphyria [Internet]. Uptodate.com. 2020 [cited 26 February 2020]. Available here.
Bonkovsky HL e. Porphyrin and heme metabolism and the porphyrias. - PubMed - NCBI [Internet]. Ncbi.nlm.nih.gov. 2020 [cited 28 February 2020]. Available here.
UpToDate [Internet]. Uptodate.com. 2020 [cited 9 June 2020]. Available here.
Sambrook J. Porphyria | Metabolic Disorders | Types, Causes, Treatment [Internet]. Patient.info. 2020 [cited 9 June 2020]. Available here.
Porphyria - British Liver Trust [Internet]. British Liver Trust. 2020 [cited 9 June 2020]. Available here.