Q: What are the few options to decrease the side effects of Neostigmine when used to relieve acute colonic pseudo-obstruction, popularly known as Ogilvie's syndrome?
Answer: Neostigmine is an acetylcholinesterase inhibitor and is very effective in patients with acute colonic pseudo-obstruction, especially patients who fail conservative measures for 2-3 days or have cecal diameter > 12 cm. Some of the side effects are bradycardia going towards asystole (atropine is recommended to be available at the bedside), seizures, restlessness, tremor, salivation, sweating, bronchoconstriction, abdominal cramps, nausea, and vomiting. Few strategies to minimize the side effects are
- Inject slowly over 5 minutes
- Keep patient supine (with bedpan to decrease the nuisance of stool passage)
- Decrease the dose to 1.5 mg or even to 0.5-1 mg in high-risk patients
- Co-administration of glycopyrrolate which is an anticholinergic agent with minimal effect on the muscarinic receptors of the colon