Drug reference
tiotropium bromide
Long-acting muscarinic antagonist (LAMA), anticholinergic · Bronchodilator
Long-acting muscarinic antagonist (LAMA), anticholinergicBronchodilator
CDSCO approved
EXCRETION
—
not curated
INTERACTIONS
—
none in our sources
PREGNANCY
—
not curated
Mechanism
Tiotropium bromide binds to all muscarinic receptor subtypes but dissociates slowly from M3 and M1 receptors, conferring kinetic selectivity. It acts as a competitive antagonist of endogenous acetylcholine (ACh) at muscarinic receptors, inhibiting the direct constrictor effect on bronchial smooth muscle mediated via the M3-Gq-PLC-IP3-Ca2+ pathway. It antagonizes vagally mediated airway tone, leading to bronchodilation and reduced mucus secretion.
Indications
COPDSevere asthma (as an additional bronchodilator when not adequately controlled with maximal ICS/LABA therapy)Bronchial asthmaCOPD (more effective than ipratropium, suitable for severe cases with FEV1<50% of predicted)
Dosing
- Adult
- 1 rotacap by inhalation OD (18 μg)
Pharmacokinetics
Duration
24+ h
Bioavailability
not absorbed from respiratory and g.i. mucosa
Side effects
Common
Dryness of the mouth (10-15%, usually disappears)
Serious
- Urinary retention (occasionally in elderly patients)
Related guidelines
Other Long-acting muscarinic antagonist (LAMA), anticholinergic drugs
Ask House about tiotropium bromide
Continue into a citation-backed clinical answer with the drug context already attached.
Textbook-sourced·Sources: KD Tripathi 7e, Goodman & Gilman 14e·Updated: 2026-05-10