Mast cell medications: Antihistamines by receptor activity

The following medications listed are available in oral or intravenous formulation. Not all medications are available in the US or Europe. Topical and inhaled medications are not included in these lists.

H1 antihistamines interfere with the action of histamine at the H1 receptor. This can help with many symptoms, including flushing, itching, hives, burning skin, nasal congestion, sneezing, constriction of airway, shortness of breath, GI cramping, diarrhea, gas, abdominal pain, tachycardia, blood pressure variability or dizziness. What symptoms are best alleviated varies with the medication; they do not all address all symptoms equally.

First generation Second and third generation Atypical antipsychotics
Alimemazine Acrivastine Aripiprazole
Azatadine Astemizole Asenapine
Benztropine Azelastine Clozapine
Bepotastine Bepotastine Iloperidone
Brompheniramine Bilastine Olanzapine
Buclizine Cetirizine Paliperidone
Captodiame Clemastine Quetiapine
Carbinoxamine Clemizole Risperdone
Chlorcyclizine Clobenztropine Ziprasidone
Chloropyramine Desloratadine Zotepine
Chlorpheniramine Ebastine
Chlorphenoxamine Emedastine
Cinnarizine Epinastine Typical antipsychotics
Clemastine Fexofenadine Chlorpromazine
Cyclizine Ketotifen Flupenthixol
Cyproheptadine Latrepirdine Fluphenazine
Dexbrompheniramine Levocabastine Perphenazine
Dexchlorpheniramine Levocetirizine Prochlorperazine
Dimenhydrinate Loratadine Thioridazine
Diphenhydramine Mebhydrolin Thiothixene
Diphenylpyraline Mizolastine
Doxylamine Rupatadine
Embramine Setastine Tetracyclic antidepressants
Etodroxizine Talastine Amoxapine
Ethylbenztropine Terfenadine Loxapine
Etymemazine Maprotiline
Flunarizine Mianserin
Histapyrrodine Tricyclic antidepressants Mirtazapine
Homochlorcyclizine Amitriptyline Oxaprotiline
Hydroxyethylpromethazine Butriptyline
Hydroxyzine Clomipramine
Isopromethazine Desipramine
Meclizine Dosulepin
Mequitazine Doxepin
Methdilazine Imipramine
Moxastine Iprindole
Orphenadrine Lofepramine
Oxatomide Nortriptyline
Oxomemazine Proptriptyline
Phenindamine Trimipramine
Pheniramine
Phenyltoloxamine
Pimethixene
Prometheazine
Propiomazine
Talastine
Thonzylamine
Tolpropamine
Tripelennamine
Triprolidine

 

H2 antihistamines interfere with the action of histamine at the H2 receptor. This helps mostly with symptoms affecting the GI tract, such as abdominal pain, nausea, and diarrhea. To a lesser extent, H2 antihistamines can decrease vasodilation.

H2 antagonists
Cimetidine
Famotidine
Lafutidine
Nizatidine
Ranitidine
Roxatidine

 

There are few H3 antihistamines and for this reason, their exact effects are largely unknown.  However, in research, H3 antihistamines modulate nerve pain and may normalize the release of several neurotransmitters, including serotonin.

The only medication with known H3 activity available for patient use as an antihistamine anywhere in the world is betahistine. It is anti-vertigo drug used mostly in treatment of Meniere’s disease and other balance disorders. Betahistine actually increases release of histamine and for this reason has been associated with the risk of severe allergic events while taking it.

A 2014 paper described for the first time the H3 reverse agonist/ selective antagonist effects of two antiarrhythmic drugs, amiodarone and lorcainide. This is a very new finding and has not been investigated yet in humans; however, this behavior would explain some of the neurologic effects of these two medications.

H3 antihistamines
Amiodarone*
Betahistine
Lorcainide*

 

Thioperamide has shown promise in research as an H3 and H4 antihistamine, but is not available for patient use.

I have seen blurbs on forums and the internet in which people state that amphetamines are H3 antagonists and doxepin is an H4 antihistamine. I cannot find any evidence that this is the case. Amphetamines interact with the transport of histamine in a very complex way, and that can theoretically interfere with the ability of cells to use histamine. However, this is not the same as a true antihistamine, and the effect of amphetamines on histamine has been difficult to quantify.

1 Response

  1. Karen Neill April 21, 2015 / 2:54 pm

    Lisa, I have no idea how you have the energy to produce this information, but I am glad that you do!!!!
    It might be worth pointing out that many people also get improvement of neurologic symptoms (especially ‘brain fog’ and headaches) from H2 antihistamines. I don’t know what the scientific evidence for this is, but the anecdotal evidence seems strong.
    Cheers, Karen

Comments are closed.