Provocholine® (methacholine chloride) is indicated for the diagnosis of bronchial airway hyperresponsiveness in subjects suspected of having asthma. The methacholine challenge test with Provocholine® provides a measure of the severity of asthma.

Provocholine® (methacholine chloride powder USP) is a parasympathomimetic (cholinergic) bronchoconstrictor agent to be administered in solution only, by inhalation, for diagnostic purposes.

Provocholine® (methacholine chloride powder USP) is a parasympathomimetic (cholinergic) bronchoconstrictor agent to be administered in solution only, by inhalation, for diagnostic purposes. Methacholine chloride is the ß-methyl homolog of acetylcholine and differs from the latter primarily in its greater duration and selectivity of action. Bronchial smooth muscle contains significant parasympathetic (cholinergic) innervation. Bronchoconstriction occurs when the vagus nerve is stimulated and acetylcholine is released from the nerve endings.

Muscle constriction is essentially confined to the local site of release because acetylcholine is rapidly inactivated by acetylcholinesterase. Compared with acetylcholine, methacholine chloride is more slowly hydrolysed by acetylcholinesterase and is almost totally resistant to inactivation by non-specific cholinesterase or pseudocholinesterase. When a solution containing Provocholine® is inhaled, subjects with current asthma are more sensitive to methacholine and bronchoconstrict at lower doses than healthy subjects.

This difference in response is the pharmacologic basis for the Provocholine® inhalation diagnostic challenge. The test is most useful diagnostically when there are current symptoms consistent with asthma and when the forced expiratory volume at one second (FEV1) is normal at>70% predicted. A normal result excludes current asthma (variable airflow limitation), but does not exclude past asthma.

Status

Provocholine® is used by practitioners worldwide in the fields of asthma and allergy and the methacholine challenge test is widely cited and accepted in practitioner guidelines (such as the American Thoracic Society's Guidelines for Methacholine and Exercise Challenge Testing -1999).

 

Registered

Approved in Canada, the United States, countries in Europe, and several other markets.

Methapharm is looking for International partners for the distribution of its Provocholine product.