Tiotropium Inhaled

Tiotropium is a once-daily long-acting muscarinic antagonist (LAMA) used in COPD and as add-on in asthma.

Classification. Long-acting antimuscarinic.

Mechanism. Slowly dissociates from M3 receptors, giving 24-hour bronchodilation.

Pharmacokinetics. Mostly renal elimination of absorbed drug. Half-life 5 to 6 days.

First-line, COPD. 18 micrograms capsule once daily by dry powder device, or 5 micrograms (2 puffs of 2.5 micrograms) once daily by soft mist inhaler.

Specialist, asthma add-on. 2.5 micrograms (2 puffs of 1.25 micrograms) once daily, adults and from 6 years.

Titration. None. No loading dose.

Contraindications. Hypersensitivity, milk protein allergy for the capsule.

Serious adverse effects. Urinary retention, glaucoma, paradoxical bronchospasm, arrhythmia.

Common adverse effects. Dry mouth, constipation.

Interactions. Other anticholinergics.

Common prescribing errors. Swallowing the capsule.

Special groups.

• Pregnancy and breastfeeding: use only if necessary.

• Older adults: caution with prostatic enlargement.

• Kidney impairment: with creatinine clearance of 60 mL/min or less, monitor closely.

• Liver impairment: no adjustment.

Formulations. Capsule for inhalation device; soft mist cartridge.

Baseline. Eye and urinary history.

Monitoring. Symptoms, exacerbations, urinary retention.

Stop and reduce rules. Stop for glaucoma symptoms or retention. Therapeutic drug monitoring is not used.

Referral and escalation. Escalate to a LABA combination for persistent symptoms.