Subcutaneous Neostigmine is Effective and Safe in the Treatment of In-Hospital Colonic Ileus

The objective of this study is to compare the efficacy and safety of subcutaneous (SQ) neostigmine to intravenous (IV) neostigmine for the treatment of in-hospital colonic ileus on outcomes such as resolution of ileus, time to stooling, and total adverse events. This is a retrospective, cohort review study of inpatients diagnosed with colonic ileus and treated with either IV or SQ neostigmine. We found that no differences in ileus resolution post-neostigmine comparing the IV (37%; n=11) to the SQ (78%, n=7) (p=0.05) groups, time to first stooling in IV vs SQ (19.5 ± 32.4 hours vs. 5.3 ± 6.4 hours, p= 0.07), need for decompressive colonoscopy (30% vs 22%, p=1.0), and need for ICU admission (28% vs 6%, p= 0.07%) in the IV vs SQ groups respectively, or adverse events (p=0.11) in the IV versus SQ neostigmine groups; although the total neostigmine dose used in the SQ group was lower (p<0.001). There was no statistically significant difference in adverse events in the IV group vs the SQ group (14% vs 11%, p=0.11). Based on these results, SQ neostigmine appears to be effective and safe in resolving colonic ileus.