Tiotropium bromide

Описание

Tiotropium is an antagonist that binds to M₁, M₂, and M₃ muscarinic acetylcholine receptors (K_ds = 0.43, 0.54, and 0.69 nM, respectively, for human receptors). It decreases acetylcholine-induced contraction of isolated guinea pig trachea in a concentration-dependent manner. In vivo, tiotropium (1 g/L inhaled aerosol) confers complete protection against acetylcholine-induced bronchospasms in anesthetized dogs. Formulations containing tiotropium have been used in the treatment of chronic obstructive pulmonary disease (COPD).

Химические свойства

White Solid

Использование

Muscarinic receptor antagonist. Bronchodilator

Определение

ChEBI: An organic bromide salt having (1alpha,2beta,4beta,5alpha,7beta)-7-[(hydroxydi-2-thienylacetyl)oxy]-9,9-dimethyl-3-oxa-9-azoniatricyclo[3.3.1.02,4]non ne as the counterion. Used (in the form of the hydrate) for maintenance treatment of airflow obstruction in patients with chronic obstructive pulmonary disease.

Общее описание

Tiotropium bromide, (1 ,2 ,4 ,7 )-7-[(hydroxidi-2-thienylacetyl)oxy]-9,9-dimethyl-3-oxa-9-azoniatricyclo[3.3.1.02,4]nonane, (Spiriva) is anantimuscarinic agent that is used in an inhalation device to deliverthe drug into the lungs. It is indicated in the treatment ofchronic obstructive pulmonary disease (COPD), includingchronic bronchitis and emphysema. The standard once-dailydose is 18 g of tiotropium.

Фармакокине?тика

Tiotropium is administered as a dry powder via inhalation using a HandiHaler, in which is placed the drug, contained in a green capsule. Patients should be cautioned not to be confused and take the medication orally. Systemic distribution following oral inhalation is minimal, essentially because of its hydrophilic character. If swallowed, only approximately 14% of the dose is eliminated in the urine, with the remainder being found in the feces. Inhaled tiotropium has a 30-minute onset of action but a much longer duration of action than ipratropium (24 versus <4 hours, respectively). Tiotropium is metabolized by both CYP3A4 and CYP2D6, followed by glutathione conjugation to a variety of metabolites. Only a very small amount is nonenzymatically hydrolyzed to inactive products.

Клиническое использование

Tiotropium is the dithienyl derivative of N-methyl scopolamine, a quaternary analogue of naturally occurring scopolamine in Atropa belladonna. It is indicated primarily for the relief of bronchospasms associated with COPD and can be considered to be a site-specific, local medication to the lung.

Побочные эффекты

Tiotropium has an adverse reaction profile similar to that of ipratropium, with dry mouth being the most common adverse effect; however, blurred vision, tachycardia, urinary difficulty, headache precipitation, and exacerbation of narrow-angle glaucoma have been reported.