What kind of antagonist is Mepyramine?

histamine H1 receptor antagonist
Mepyramine, a histamine H1 receptor antagonist, inhibits the metabolic activity of rat and human P450 2D forms.

How does Mepyramine affect efficacy and potency of histamine?

Mepyramine competes with histamine for binding at H1-receptor sites on the effector cell surface, resulting in suppression of histaminic edema, flare, and pruritus. The sedative properties of Mepyramine occur at the subcortical level of the CNS.

Are antihistamines H1 antagonists?

H1 Antagonists (second-generation antihistamines) Commonly used H1 antagonists currently available in the United States are cetirizine, levocetirizine, desloratadine, loratadine, and fexofenadine.

How does Mepyramine block histamine?

Mepyramine, also known as pyrilamine, is a first generation antihistamine, targeting the H1 receptor as an inverse agonist. H 1 -receptor antagonists are the drugs that selectively bind to but do not activate histamine H 1 receptors, thereby blocking the actions of endogenous histamine.

How is mepyramine used as a H1 receptor antagonist?

In human hepatic microsomes, mepyramine inhibited the debrisoquine 4-hydroxylation activity catalyzed by P450 2D6. These results indicate that histamine H1 receptor antagonists such as mepyramine are potent inhibitors of P450 2D forms because of their high affinity for these enzymes.

Is it safe to use mepyramine for allergies?

WARNING: This product is for research use only, not for human or veterinary use. Description: Mepyramine, a histamine H1 antagonist. It has mild hypnotic properties and some local anesthetic action and is used for allergies (including skin eruptions) both parenterally and locally. It is a common ingredient of cold remedies.

What kind of anticholinergic activity does mepyramine have?

The medication has negligible anticholinergic activity, with 130,000-fold selectivity for the histamine H 1 receptor over the muscarinic acetylcholine receptors (for comparison, diphenhydramine had 20-fold selectivity for the H 1 receptor). It was patented in 1943 and came into medical use in 1949.

Is there such a thing as an antihistamine h 1 antagonist?

Agents where the main therapeutic effect is mediated by negative modulation of histamine receptors are termed antihistamines; other agents may have antihistaminergic action but are not true antihistamines. In common use, the term “antihistamine” refers only to H 1 -antihistamines.