Description
Ipratropium bromide is a quaternary ammonium congener of atropine and is an anticholinergic compound approved for use as a bronchodilator. Anticholinergic agents produce bronchodilatation by antagonizing the activity of acetylcholine at the level of its receptor, particularly those found on airway smooth muscle in the large, central airways. The onset of action of ipratropium is relatively slow (20 minutes), and the peak effect occurs at 60 minutes.1 Ipratropium, unlike atropine, is poorly absorbed across mucous membranes and has little toxicity at the usual doses.
Chemical Properties
White or almost white, crystalline powder.
Uses
Ipratropium bromide monohydrate has been used for the inhibition of peripheral muscarinic receptors in rats.
Definition
ChEBI: The monohydrate form of ipratropium bromide. An anticholinergic drug, ipratropium bromide blocks the muscarinic cholinergic receptors in the smooth muscles of the bronchi in the lungs. This opens the bronchi, so providing relief in chronic obstructive pulm
nary disease and acute asthma.
brand name
Atrovent (Boehringer Ingelheim).
Biochem/physiol Actions
Ipratropium bromide monohydrate is a nonselective muscarinic acetylcholine receptor antagonist and a bronchodilator. In nebulized form, it is used for treating asthma and obstructive pulmonary diseases. It acts as a β2 adrenoreceptor agonist. Ipratropium bromide monohydrate is an anticholinergic agent and competes with acetylcholine. It promotes bronchodilation by stimulating sympathetic pathways.
Clinical Use
Anticholinergic bronchodilator:
Reversible airways obstruction, particularly in
COPD
Side effects
Previous severe allergic reaction symptoms upon using ipratropium or atropine and its other derivatives, such as angioedema, urticaria, severe shortness of breath, oropharyngeal edema, and ultimately anaphylaxis is a contraindication to ipratropium use.
Ipratropium aerosols can cause bronchospasms (paradoxical), which usually happens upon the initial use of this medication
Metabolism
After inhalation, around 10-30% of a dose is deposited
in the lungs where it exerts its therapeutic effect. Only
a small amount of ipratropium reaches the systemic
circulation. The majority of a dose is swallowed but
is poorly absorbed from the gastrointestinal tract.
Ipratropium and its metabolites are eliminated in the
urine and faeces.
