SPIRIVA RESPIMAT
Clinical safety rating: caution
Comprehensive clinical and safety monograph for SPIRIVA RESPIMAT (SPIRIVA RESPIMAT).
Long-acting muscarinic antagonist (LAMA) that inhibits acetylcholine at M3 receptors in bronchial smooth muscle, leading to bronchodilation.
| Metabolism | Primarily non-enzymatic hydrolysis to inactive metabolites; minor CYP2D6 and CYP3A4 involvement. |
| Excretion | Renal excretion (60-70% unchanged) and biliary/fecal excretion (30-40%) after IV administration; after inhalation, most of the swallowed dose is eliminated fecally. |
| Half-life | Terminal elimination half-life of 27 hours after inhalation (range 13-50 hours), supporting once-daily dosing due to prolonged receptor binding. |
| Protein binding | ~72%, primarily to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 32 L/kg (IV), indicating extensive tissue distribution; steady-state Vd ~1850 L after inhalation. |
| Bioavailability | Inhalation: ~19-22% of the emitted dose (mostly from lung deposition; oral bioavailability <5%). |
| Onset of Action | Inhalation: 30 minutes (bronchodilation); peak effect at 1.5-3 hours. |
| Duration of Action | >24 hours (bronchodilation sustained throughout the dosing interval; no evidence of tolerance). |
| Molecular Weight | 472.4 |
| Action Class | Anticholinergic Bronchodilator |
2 actuations (2.5 mcg tiotropium/actuation) once daily by oral inhalation.
| Dosage form | SPRAY |
| Renal impairment | No dose adjustment required for GFR ≥30 mL/min. For GFR <30 mL/min, use only if benefit outweighs risk; no specific dose adjustment provided. |
| Liver impairment | No dose adjustment required for mild to moderate hepatic impairment (Child-Pugh A or B). Not studied in severe hepatic impairment (Child-Pugh C). |
| Pediatric use | Not recommended for pediatric patients (safety and efficacy not established in children). |
| Geriatric use | No dose adjustment required based on age. Monitor for anticholinergic effects (e.g., constipation, urinary retention) in elderly patients. |
| 1st trimester | Limited human data; animal studies show no teratogenic effects at relevant doses. Use only if clearly needed. |
| 2nd trimester | Limited human data; no evidence of fetal harm from inhaled anticholinergics. Use only if clearly needed. |
| 3rd trimester | Limited human data; potential risk of uterine relaxation and bleeding? Use only if clearly needed. |
Clinical note
Comprehensive clinical and safety monograph for SPIRIVA RESPIMAT (SPIRIVA RESPIMAT).
| Placental transfer | Molecular weight suggests potential for placental transfer; however, systemic exposure is low after inhalation. Animal studies show minimal transfer. |
| Breastfeeding | Not known if tiotropium is excreted in human milk. Due to low systemic absorption from inhaled route, risk to infant is likely low. Caution in nursing mothers. |
■ FDA Black Box Warning
Not for initial treatment of acute episodes of bronchospasm or for acute deterioration of COPD or asthma; may cause paradoxical bronchospasm.
| Common Effects | Dry mouth, Pharyngitis, Sinusitis, Upper respiratory tract infection, Cough, Headache, Dysphonia |
| Serious Effects | Paradoxical bronchospasm, Immediate hypersensitivity reactions (angioedema, urticaria, rash, pruritus), Worsening of narrow-angle glaucoma, Urinary retention (especially in patients with prostatic hyperplasia or bladder-neck obstruction), Atrial fibrillation or flutter |
Hypersensitivity to tiotropium or any excipientImmediate hypersensitivity reactions including anaphylaxis
| Precautions | Paradoxical bronchospasm, Immediate hypersensitivity reactions, Worsening of narrow-angle glaucoma, Worsening of urinary retention, Use in patients with severe renal impairment (CrCl <30 mL/min) with caution, Not studied in patients with severe hepatic impairment |
Loading safety data…
| Lactation Rating |
| L3 (Moderately Safe) |
| Teratogenic Risk | FDA Pregnancy Category B. No evidence of teratogenicity in animal studies. No adequate human studies; risk cannot be excluded. Theoretical risk of anticholinergic effects in third trimester: decreased fetal heart rate variability, transient neonatal respiratory depression, and decreased neonatal gut motility. |
| Fetal Monitoring | Maternal: pulmonary function tests, heart rate, signs of worsening COPD/asthma. Fetal: third-trimester ultrasound for amniotic fluid volume (anticholinergic effect), fetal heart rate monitoring if high dose or maternal comorbidity. |
| Fertility Effects | No adverse effects on fertility observed in animal studies. No human data. Theoretical concern: anticholinergic effects may alter cervical mucus or fallopian tube motility, but clinical significance unknown. |
| Food/Dietary |
| No clinically significant food interactions. Avoid grapefruit juice only if patient has comorbid conditions requiring CYP3A4 caution, but tiotropium is minimally metabolized by CYP3A4; no specific dietary restrictions. |
| Clinical Pearls | Do not use for acute bronchospasm. Administer once daily at the same time of day. Instruct patient not to exhale into mouthpiece. Do not shake canister before use. Priming requires 3 test sprays; if not used for >3 days, reprime with 1 test spray. May cause paradoxical bronchospasm. Monitor for anticholinergic effects: dry mouth, glaucoma, urinary retention. Inhaled corticosteroids should be continued unchanged in COPD. |
| Patient Advice | Use exactly as prescribed: 2 inhalations once daily. · Do not use for sudden breathing problems; have rescue inhaler available. · Prime the inhaler before first use and after >3 days of non-use. · Close lips tightly around mouthpiece, breathe in slowly and deeply. · Hold breath for 10 seconds after inhalation, then exhale slowly. · Rinse mouth with water after each use to prevent thrush. · Avoid spraying into eyes; risk of eye pain or blurred vision. · Report worsening symptoms, vision changes, or difficulty urinating. · Store upright at room temperature; do not freeze or expose to heat. |