We discuss the microhollow cathode discharge (MHCD) as a microreactor for endothermic reactions. The high-peak neutral temperature, power density, and ion density of MHCDs may provide a highly reactive environment for these chemistries. Decomposition of ammonia and carbon dioxide are examined Conversion is found to vary strongly based mainly on residence time. The results are fit to a plug-flow reactor model, and an effective reaction temperature is calculated. The effective reaction temperature in both cases exceeds 2000 K and suggests that thermal processes play an important role in decomposition.