H1 antagonist

H1 histamine receptor antagonist

If BBB-crossing:
Sedation
Weight gain (↑ intake, ↓ expenditure, ↑ fat storage)
Anxiolytic and antiemetic effects
↓ seizure threshold
The principal mechanism of sedation by antidepressants/antipsychotics
act at hypothalamus and cerebral cortex
suppress the histamine-mediated wakefulness network
The single strongest predictor of weight gain across antipsychotic and antidepressant classes
Anti-allergy effects
reduced inflammatory mediator release
decreased vascular permeability

Drugs with this mechanism (99)

7-OH loxapine 8-OH-Amoxapine Loxapine inhaled Amitriptyline Amoxapine Aripiprazole Aripiprazole lauroxil LAI Aripiprazole lauroxil LAI Aripiprazole monohydrate LAI Aripiprazole monohydrate LAI Asenapine Asenapine transdermal Azelastine Benztropine Brexpiprazole Brompheniramine Cariprazine Cetirizine Chlorpheniramine Chlorpromazine Chlorpromazine injection Clomipramine Clozapine Cyclobenzaprine Cyproheptadine Dehydroaripiprazole Desipramine Desloratadine Desmethylcariprazine Desmethylclomipramine (Desmethyl-) mirtazapine Didesmethylcariprazine Dimenhydrinate Diphenhydramine Diphenhydramine injection Doxepin Doxylamine Clozapine ODT Fexofenadine Fluphenazine Fluphenazine decanoate LAI Fluphenazine injection Hydroxynefazodone Hydroxyzine HCl Hydroxyzine IM Hydroxyzine pamoate Imipramine Ketotifen Levocetirizine Loratadine Loxapine Lurasidone Maprotiline Meclizine Melperone Mianserin Mirtazapine Nefazodone Norclozapine Nordoxepin Norquetiapine Nortriptyline Olanzapine Olanzapine IM Olanzapine pamoate LAI Olanzapine SubQ LAI Olopatadine Orphenadrine Oxybutynin Oxybutynin ER Paliperidone Paliperidone palmitate LAI Paliperidone palmitate LAI Paliperidone palmitate LAI Paliperidone palmitate LAI Perphenazine Prochlorperazine Prochlorperazine injection Promethazine Promethazine injection Protriptyline Quetiapine Risperidone Risperidone LAI Risperidone LAI Risperidone LAI Risperidone LAI Risperidone LAI Quetiapine XR Doxepin low-dose (insomnia) Thioridazine Thiothixene Trazodone Trifluoperazine Trimethobenzamide Trimipramine Clozapine oral suspension Ziprasidone Ziprasidone IM

Self-check

How can central H1 antagonism change energy expenditure?
It decreases expenditure.
How does BBB-crossing H1 antagonism affect seizure threshold?
It lowers it.

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