Antihistamines

Author: Prof. Dr. med. Peter Altmeyer

All authors of this article

Last updated on: 29.10.2020

Dieser Artikel auf Deutsch

Synonym(s)

H1 antagonists; Histamine receptor antagonists

Definition
This section has been translated automatically.

Substances that attenuate or cancel the effects of histamine by reversible binding to histamine receptors.

The H1-antagonists are distinguished:

Pharmacodynamics (Effect)
This section has been translated automatically.

Competitive inhibition of H1 receptors, diaminooxidase inhibition, inhibition of potassium leakage from the cells. Histamine-mediated effects such as vasodilation, increased vascular permeability via inhibition of the release of proinflammatory cytokines such as IL-4, IL-6, Il-8,IL-13 from mast cells and the expression of the adhesion molecule P-selectin from endothelial cells are inhibited. The spectrum of action of H1 antihistamines thus includes anti-allergic and antiphlogistic effects.

Indication
This section has been translated automatically.

Allergic reactions, pruritus, atopic eczema, allergic rhinitis, bronchial asthma.

Undesirable effects
This section has been translated automatically.

Sedation (inability to drive! with the H1 antagonists), dry mouth (due to anticholinergic effect), gastrointestinal disorders, central nervous disorders. The photosensitizing potency of the newer non-sedating antihistamines is not proven.

Interactions
This section has been translated automatically.

Central steaming pharmaceuticals, alcohol (effect intensification).

Contraindication
This section has been translated automatically.

Pregnancy, infants, bladder neck adenoma.

Note(s)
This section has been translated automatically.

Before starting antihistaminergic therapy, it is recommended that all patients undergo a risk assessment according to the CONGA report (acronym for Consensus Group on New-Generation Antihistamines):
  • Does any form of heart disease already exist? If so, an antihistamine with little or no interaction with the cardiac potassium channels should be chosen.
  • Is there a co-medication with the following preparations: macrolides, opiates, imidazoles, psychotropic drugs, anti-malaria drugs? If so, an accurate re-evaluation of the medication should be carried out and the combination of QT time prolonging preparations should be done carefully and only if strictly indicated.
  • Are there other risk factors such as liver diseases, electrolyte shifts, special potassium-rich diets? If so, treatment of the underlying diseases and strict indication for the prescription of the antihistamine.

Literature
This section has been translated automatically.

  • Netzwerk aktuell (2006) Photosensitization through antihistimanics. Medication telegram 37: 60

Authors

Last updated on: 29.10.2020