ROBINUL
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ROBINUL (ROBINUL).
Antimuscarinic; competitively antagonizes acetylcholine at muscarinic receptors, inhibiting parasympathetic nerve impulses.
| Metabolism | Hepatic (minor); primarily excreted unchanged in urine. |
| Excretion | Biliary/fecal elimination is the primary route (approximately 80-85% of a dose is recovered in feces as unchanged drug and metabolites); renal excretion accounts for ~15-20% (mostly unchanged drug and active metabolite). |
| Half-life | Terminal elimination half-life is approximately 3–4 hours in healthy adults; in elderly or patients with renal impairment, half-life may be prolonged (up to 10 hours). Clinical context: Steady-state achieved within 24 hours; clinically insignificant accumulation with repeated dosing every 4–6 hours. |
| Protein binding | ~50% bound to plasma proteins (primarily albumin). |
| Volume of Distribution | 3–4 L/kg; indicates extensive tissue distribution (e.g., lung, liver, kidney) and poor CNS penetration due to quaternary ammonium structure. |
| Bioavailability | Oral: approximately 5–10% due to extensive first-pass metabolism; intramuscular: nearly 100%. |
| Onset of Action | Intravenous: 1–2 minutes; Intramuscular: 10–15 minutes; Oral: 30–60 minutes. |
| Duration of Action | Intravenous/Intramuscular: 4–6 hours; Oral: 3–4 hours. Note: Duration may be shorter in elderly or debilitated patients; antisialagogue effect may last up to 7 hours at higher doses. |
| Molecular Weight | 362.36 Da |
1-2 mg orally 3-4 times daily; 0.1-0.2 mg intramuscular or intravenous every 6-8 hours as needed.
| Dosage form | INJECTABLE |
| Renal impairment | No specific dose adjustment recommended per manufacturer; use caution in severe renal impairment (CrCl <30 mL/min) due to potential accumulation. |
| Liver impairment | No specific guidelines; use with caution in Child-Pugh C cirrhosis due to reduced clearance. |
| Pediatric use | Oral: 0.01-0.02 mg/kg per dose, up to 0.2 mg/kg/day divided every 6-8 hours; rectal: 0.01-0.02 mg/kg per dose every 12 hours. |
| Geriatric use | Initiate at lower end of dosing range (e.g., 0.5 mg orally 2-3 times daily) due to increased anticholinergic sensitivity and risk of cognitive impairment; titrate slowly. |
| 1st trimester | Use only if clearly needed; anticholinergic effects may cause fetal tachycardia. Animal studies show no teratogenic effects but human data insufficient. |
| 2nd trimester | Use only if clearly needed; monitor for fetal heart rate changes. Possible association with meconium ileus in cystic fibrosis patients. |
| 3rd trimester | Avoid near term due to risk of neonatal anticholinergic effects (e.g., ileus, tachycardia). |
Clinical note
Comprehensive clinical and safety monograph for ROBINUL (ROBINUL).
| Placental transfer | Crosses placenta; studies show fetal serum levels approximately 70% of maternal levels. |
| Breastfeeding | Excreted into breast milk in small amounts; unlikely to cause adverse effects in infants. However, monitor for anticholinergic symptoms (e.g., irritability, constipation). |
■ FDA Black Box Warning
None
| Serious Effects |
Hypersensitivity to glycopyrrolate or any componentMyasthenia gravis (unless used for cholinergic crisis)Severe ulcerative colitisObstructive uropathyToxic megacolonGlaucoma (narrow-angle)Tachyarrhythmias
| Precautions | Use with caution in patients with coronary artery disease, congestive heart failure, arrhythmias, hypertension, hyperthyroidism, or prostatic hypertrophy., May exacerbate glaucoma., Monitor for anticholinergic effects (e.g., dry mouth, blurred vision, urinary retention). |
| Food/Dietary | No significant food interactions. Avoid excessive caffeine as it may increase side effects like nervousness and rapid heartbeat. |
Loading safety data…
| Lactation Rating |
| L3 (Moderately Safe) |
| Teratogenic Risk | Pregnancy Category B. No evidence of teratogenicity in animal studies; inadequate human studies. Avoid use in first trimester if possible; use only if clearly needed in second and third trimesters due to potential anticholinergic effects on fetus (e.g., tachycardia, meconium ileus). |
| Fetal Monitoring | Monitor maternal heart rate and blood pressure for anticholinergic effects; monitor fetal heart rate during labor if used parenterally due to risk of tachyarrhythmias. |
| Fertility Effects | No known adverse effects on fertility in animal studies. Anticholinergic effects may reduce cervical mucus production, potentially affecting sperm transport; clinical significance unknown. |
| Clinical Pearls |
| Use with caution in patients with glaucoma, urinary retention, or gastrointestinal obstruction. May cause heat stroke due to suppressed sweating. Antagonize effects of anticholinesterases. Use lower doses in elderly due to increased CNS sensitivity. |
| Patient Advice | Avoid alcohol and other CNS depressants as they may increase drowsiness. · Drink plenty of fluids to prevent constipation and dry mouth. · Do not drive or operate machinery until you know how this medication affects you. · Call your doctor if you experience difficulty urinating or eye pain. · Use sugar-free gum or candy for dry mouth. |