Learn to spot the
signs & symptoms of AHP*

AHP Features a
combination of Symptoms

In addition to severe, diffuse abdominal pain without fever or leukocytosis, other common symptoms of AHP include nausea and vomiting, limb weakness or pain, anxiety, confusion, and skin lesions on sun-exposed areas (HCP and VP only). Tachycardia and hyponatremia are often present in acute attacks of AHP.1,2,7

These symptoms reflect neurotoxic effects across the autonomic, peripheral, and central nervous systems. Patients may experience one characteristic symptom or multiple symptoms that may lead to a diagnosis1,2:

Acute hepatic porphyria symptoms


    anxiety, depression, confusion, seizures, hallucinations, insomnia



    muscle weakness, neuropathic pain in limbs, sensory loss, paralysis, fatigue, respiratory paralysis



    nausea and vomiting, hypertension, tachycardia, constipation, severe diffuse abdominal pain, diarrhea, pain in back or chest


    Cutaneous symptoms1,5

    lesions on sun-exposed skin occur only in hereditary coproporphyria (HCP), variegate porphyria (VP)


    Other Manifestations2,10

    hyponatremia, dark or reddish urine

As HCPs working with porphyria patients, it’s critical that we remember many are suffering from mentally-impairing brain fog that could also be a warning sign of an attack, and makes the caregiver’s role so critical.

Dr Robert Desnick
Dr. R. J. Desnick, Ph.D, M.DDean for Genetics and Genomic Medicine, Icahn School of Medicine at Mount Sinai

Manifestations of AHP

AHP can be characterized by potentially life-threatening attacks and, for some patients, chronic debilitating symptoms that negatively impact daily functioning and quality of life. Acute attacks in genetically predisposed patients are frequently preceded by environmental or hormonal precipitating factors.1,6,8

In a large natural history study of patients with recurrent attacks, 65% of patients reported chronic symptoms (including pain), and 46% reported experiencing symptoms every day.8

Recurrent attacks in EXPLORE were defined as ≥3 attacks within 12 months or prophylactic use of hemin or GnRH analog.8

Precipitating factors of acute attacks may include:1,5,10,11

Certain medications can trigger acute hepatic porphyria attacks
The use of some medications in the following drug classifications:
  • Anesthetics
  • Oral contraceptives
  • Anticonvulsants
  • Antihistamines
  • Antihyperglycemics
  • Antimicrobials
  • Hormones
  • Migraine drugs
  • Sedatives

Review a more complete list of medications considered unsafe:

American Porphyria Foundation Drug Database: http://www.porphyriafoundation.com/drug-database

Hormonal fluctuations during the menstrual cycle can trigger acute hepatic porphyria attacks
Hormonal fluctuations during the menstrual cycle§
Extreme dieting can trigger acute hepatic porphyria attacks
Extreme dieting
Excessive alcohol consumption can trigger acute hepatic porphyria attacks
Excessive alcohol consumption
Smoking can trigger acute hepatic porphyria attacks
Stress can trigger acute hepatic porphyria attacks
Stress caused by:
  • Infections
  • Surgery
  • Physical exhaustion
  • Emotional exhaustion

Fewer than 10% of patients experience attacks without any identifying precipitating factors.2
§Hormones are at their highest fluctuation 2 weeks before a woman's menstrual cycle begins.

AHP Can Be Misdiagnosed
as More Common Diseases

The signs and symptoms of AHP can mimic those of numerous common diseases, such as irritable bowel syndrome, Crohn's disease, endometriosis, fibromyalgia, and psychiatric disorders. These similarities can lead to misdiagnoses.9,13

In a retrospective review of 546 AHP patients’ charts submitted by 175 healthcare providers from the US, EU, Canada, and Japan, 26% of patients with AHP were initially misdiagnosed.12

Be Aware of Similar Symptoms9,12,13

Acute hepatic porphyria can show similar symptoms to other gastrointestinal disorders such as Crohn's disease, irritable bowel syndrome or IBS, acute gastroenteritis with vomiting, and hepatitis
Acute hepatic porphyria can show similar symptoms to neurological and neuropsychiatric disorders such as fibromyalgia, Guillain-Barre syndrome, and psychosis
Acute hepatic porphyria can show similar symptoms to gynecological disorders such as endometriosis
Acute hepatic porphyria can show similar symptoms to acute abdomen conditions such as appendicitis, cholecystitis, peritonitis, pancreatitis, and intestinal occclusion

Delayed Diagnoses Can Impact Patients’ Health and Long-Term Well-Being1,10,14

Long-term complications of AHP may include chronic hypertension, chronic kidney disease, hepatocellular carcinoma, psychological problems, and risk of premature death from acute attacks.

An important goal in the management of AHP is preventing irreversible long-term damage.


Diagnosis of acute hepatic porphyria can take up to 15 years from symptom onset

Delayed diagnosis and misdiagnoses can lead to unnecessary procedures. In fact, even in diagnosed AHP patients hospitalizations were common. One study found that patients with AHP had a median of 2 attacks and median of 1 hospitalization in the prior year. In another study, patients with recurrent attacks of AHP had a mean 82 days (range: 10 to 374) of hospitalization over a mean observation time of 21 years.1,12,14,16,17

Acute hepatic porphyrias put deep strain on family relationships. Patients often miss family outings, can’t help with chores or contribute financially, and often feel like a burden to their loved ones, adding emotional pain to the physical.

Dr. Karl Anderson
Dr. Karl E. Anderson, M.D., FACP Professor, Departments of Preventive Medicine and Community Health, and Internal Medicine (Division of Gastroenterology)

AHP Reduces Quality of Life (QoL)

AHP is a debilitating disease with a significant impact on patients’ daily lives and social functioning, both during and in between attacks. In a study of AIP (the most common subtype of AHP) patients with recurrent acute attacks, 63% reported a negative impact on relationships or social roles, 74% reported interference with walking, and 84% reported impaired ability to work.6

Acute hepatic porphyria impact on relationships, education and work, and walking; Acute hepatic porphyria impact on education and work; Acute hepatic porphyria impact on walking

||As reported in a population with acute intermittent porphyria with multiple attacks (3 or more) within the last year.6

Long-term chronic pain, emotional stress, comorbid depression and anxiety, and fear of unpredictable attacks contribute to a lower QoL for some patients with AHP.6,18,19

See How Porphyria Impacts the Lives of Real Patients

Watch the video below to learn about Colin's difficult journey to correct diagnosis.

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