ENLON-PLUS
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ENLON-PLUS (ENLON-PLUS).
Enlon-Plus (neostigmine methylsulfate and glycopyrrolate) is a combination of a reversible acetylcholinesterase inhibitor (neostigmine) and an anticholinergic agent (glycopyrrolate). Neostigmine inhibits acetylcholinesterase, increasing acetylcholine concentration at cholinergic synapses, enhancing neuromuscular transmission. Glycopyrrolate counteracts muscarinic side effects (e.g., bradycardia, excessive secretions) without affecting nicotinic actions.
| Metabolism | Neostigmine: Hydrolyzed by cholinesterases and metabolized in the liver via microsomal enzymes. Glycopyrrolate: Not significantly metabolized; eliminated unchanged in urine and bile. |
| Excretion | Renal: 70% unchanged; biliary/fecal: 30% as metabolites. |
| Half-life | Terminal elimination half-life: 3.5–4.5 hours (prolonged in hepatic impairment). |
| Protein binding | Plasma protein binding: 55–65%, primarily to albumin. |
| Volume of Distribution | Vd: 0.8–1.2 L/kg, indicating distribution into total body water. |
| Bioavailability | Oral: 70–80% (first-pass effect); IM: 100%. |
| Onset of Action | IV: 1–2 min; IM: 5–10 min; Oral: 30–60 min. |
| Duration of Action | IV: 15–30 min; IM: 30–60 min; Oral: 3–4 hours. |
1 to 2 mL (0.5 to 1 mg neostigmine methylsulfate with 0.2 to 0.4 mg glycopyrrolate) IV over 1 minute; may repeat in 10-15 minutes if needed; maximum total dose: 5 mL.
| Dosage form | INJECTABLE |
| Renal impairment | CrCl 10-50 mL/min: Use 50% of dose. CrCl <10 mL/min: Use 25% of dose. Adjust based on neostigmine component due to renal excretion. |
| Liver impairment | No specific adjustment required; neostigmine minimally hepatically metabolized. |
| Pediatric use | 0.04 mg/kg neostigmine methylsulfate with 0.02 mg/kg glycopyrrolate IV; may repeat in 10-15 minutes if needed; maximum single dose: 2 mL. |
| Geriatric use | Use with caution; consider lower initial doses due to potential renal impairment; monitor for bradycardia and excessive cholinergic effects. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for ENLON-PLUS (ENLON-PLUS).
| Breastfeeding | Not recommended. Unknown M/P ratio. Atropine and pralidoxime (components of ENLON-PLUS) may enter breast milk; potential for infant anticholinergic effects and gastrointestinal disturbances. |
| Teratogenic Risk | First trimester: No adequate studies in pregnant women; animal studies not available. Risk cannot be ruled out. Second/third trimester: Potential fetal toxicity (respiratory depression, bradycardia) if used near term. Avoid use during labor due to risk of neonatal respiratory depression. |
| Fetal Monitoring |
■ FDA Black Box Warning
Should be used only when facilities for immediate endotracheal intubation, artificial respiration, and oxygen therapy are available. Bradycardia and cardiac arrest have occurred. Administer in the presence of an anesthesiologist or other qualified clinician.
| Serious Effects |
Known hypersensitivity to neostigmine, glycopyrrolate, or any component. Contraindicated in patients with peritonitis, mechanical intestinal obstruction, or urinary tract obstruction.
| Precautions | Risk of severe bradycardia, hypotension, and cardiac arrest. Use caution in patients with asthma, epilepsy, bradyarrhythmias, recent myocardial infarction, or hyperthyroidism. May increase bronchial secretions. Avoid in patients with mechanical obstruction of the gastrointestinal or urinary tract. |
Loading safety data…
| Monitor maternal heart rate, blood pressure, oxygen saturation. Fetal heart rate monitoring recommended during maternal treatment. Assess for signs of cholinergic crisis (excessive salivation, lacrimation, bronchial secretions). |
| Fertility Effects | No human data. Animal studies not conducted. Potential anticholinergic effects (e.g., dry mucous membranes, altered cervical mucus) may theoretically affect fertility. |