What is the treatment for histamine intolerance?

Treatment for Histamine Intolerance

The primary treatment for histamine intolerance is a combination of H1 and H2 antihistamines, along with a low-histamine diet to reduce symptoms and improve quality of life. 1

Pharmacological Management

First-line Treatments:

• H1 Receptor Antihistamines

  • Nonsedating H1 antihistamines (such as fexofenadine and cetirizine) are generally preferred and can be increased to 2-4 times the standard dose for better symptom control 1
  • These medications help reduce dermatologic manifestations like flushing and pruritus, as well as tachycardia and abdominal discomfort 1

• H2 Receptor Antihistamines

  • H2 blockers (ranitidine, famotidine, cimetidine) can be used as first-line therapy for gastrointestinal symptoms 1
  • They also help H1 antihistamines attenuate cardiovascular symptoms when used in combination 1

Second-line Treatments:

• Cromolyn Sodium (oral formulation)

  • Reduces abdominal bloating, diarrhea, and cramps 1
  • Benefits may extend to neuropsychiatric manifestations 1
  • Should be introduced at the lowest dose and gradually increased to 200 mg 4 times daily (before meals and at bedtime) 1
  • Patients should be counseled that onset of action can be delayed and should be taken for at least 1 month before evaluating efficacy 1

• Doxepin

  • A potent H1 and H2 antihistamine with tricyclic antidepressant activity 1
  • May reduce central nervous system manifestations 1
  • Use with caution due to potential sedation and cognitive effects, especially in elderly patients 1

• Leukotriene Inhibitors

  • Montelukast or zileuton may reduce bronchospasm or gastrointestinal symptoms, particularly if urinary LTE4 levels are increased 1
  • Most efficacious for dermatologic symptoms when used in conjunction with H1 antihistamines 1

• Cyproheptadine

  • A sedating H1 antihistamine with extended anticholinergic and antiserotonergic activities 1
  • Particularly helpful for gastrointestinal symptoms 1

For Severe or Refractory Symptoms:

• Corticosteroids

  • May be useful for refractory symptoms at an initial oral dosage of 0.5 mg/kg/day, followed by a slow taper over 1-3 months 1
  • Not recommended for long-term use due to side effects 1

• Omalizumab

  • May prevent anaphylactic episodes in some patients with mast cell activation syndrome 1
  • Mechanism of action involves binding free IgE, preventing its binding to FcεRI 1

Dietary Management

• Low-Histamine Diet

  • Considered the gold standard for treating histamine intolerance 2
  • A good response to such a diet is considered confirmation of histamine intolerance 2
  • Unanimously recommended to avoid fermented foods (cheese, wine, beer, fermented sausages, pickled cabbage) 3, 4
  • Dietary restrictions should be individualized based on symptom triggers 3, 5

• Common Foods to Avoid:

  • Fermented foods and beverages (cheese, wine, beer, sauerkraut) 3, 4
  • Fish, especially if not fresh 4
  • Hard-cured sausages 4
  • Some fruits high in putrescine (citrus fruits, bananas) that may interfere with histamine degradation 3

Important Considerations and Pitfalls

• Avoid First-Generation Antihistamines When Possible

  • First-generation H1 antihistamines (diphenhydramine, hydroxyzine, chlorpheniramine) can cause sedation, impair driving ability, and lead to cognitive decline, particularly in elderly patients 1
  • There is also concern about their use in patients prone to cardiovascular events 1

• Diagnostic Challenges

  • Histamine intolerance diagnosis requires a complex, time-demanding multidisciplinary approach 2
  • Symptoms can be inconsistent and varied in the same individual following similar stimuli 2
  • Important to rule out other conditions with similar presentations, particularly allergies 6

• Supplementation

  • DAO (diamine oxidase) supplementation may be considered as subsidiary treatment for individuals with intestinal DAO deficiency 2
  • Should be used alongside dietary measures 2

• Duration of Treatment

  • If antihistamines are indicated, treatment should be conscious and time-limited 2
  • Second or third generation H1 antihistamines should take precedence 2

• Avoid Overly Restrictive Diets

  • Many low-histamine diets exclude a wide variety of foods, which can significantly impact quality of life without providing long-term benefit 5
  • An individual diagnostic and therapeutic approach is recommended to minimize unnecessary food avoidance 5

• For Acute Management of Severe Reactions:

  • Epinephrine autoinjector for patients with history of systemic anaphylaxis or airway angioedema 1
  • Bronchodilator (albuterol) for symptoms of bronchospasm 1
  • Supine positioning for those with recurrent hypotensive episodes 1