What are the signs and symptoms of Acute intermittent porphyria? Some people who inherit the gene for AIP never develop symptoms and are said to have "latent" AIP. Those individuals that present with symptoms usually do so after puberty, probably because of hormonal influences, although other activating factors include: alcohol, drugs (e.g., barbiturates, steroids, sulfa-containing antibiotics), chemicals, smoking, reduced caloric intake, stress, and travel. Symptoms usually last several days, but attacks for which treatment is not received promptly may last weeks or months. Abdominal pain, which is associated with nausea and can be severe, is the most common symptom and usually the first sign of an attack. Other symptoms may include :  Gastrointestinal issues (e.g., nausea, vomiting, constipation, diarrhea, abdominal distention, ileus)  Urinary tract issues (e.g., urinary retention, urinary incontinence, or dysuria)  Neurological issues (e.g., muscle weakness in the arms or legs, paralysis)  Psychiatric issues (e.g., insomnia, hysteria, anxiety, apathy or depression, phobias, psychosis, agitation, delirium, somnolence, or coma) Individuals with AIP have an increased risk of developing hepatocellular carcinoma; some develop kidney failure. The Human Phenotype Ontology provides the following list of signs and symptoms for Acute intermittent porphyria. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abdominal pain 90% Abnormality of urine homeostasis 90% Anorexia 90% Insomnia 90% Myalgia 90% Nausea and vomiting 90% Seizures 90% Arrhythmia 50% Constipation 50% Hyperhidrosis 50% Hypertensive crisis 50% Paresthesia 50% Abnormality of lipid metabolism 7.5% Arthralgia 7.5% Cranial nerve paralysis 7.5% Diaphragmatic paralysis 7.5% Hallucinations 7.5% Hemiplegia/hemiparesis 7.5% Hyponatremia 7.5% Neoplasm of the liver 7.5% Reduced consciousness/confusion 7.5% Renal insufficiency 7.5% Weight loss 7.5% Acute episodes of neuropathic symptoms - Anxiety - Autosomal dominant inheritance - Depression - Diarrhea - Dysuria - Elevated urinary delta-aminolevulinic acid - Hepatocellular carcinoma - Hypertension - Nausea - Paralytic ileus - Psychotic episodes - Respiratory paralysis - Tachycardia - Urinary incontinence - Urinary retention - Vomiting - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.