Aims Croup is a clinical syndrome which included inspiratory stridor, coughing with a dog-like sound, noise obstruction and respiratory distress symptoms. This present study was conducted to compare the effects of cold drink and dexamethasone, and the effects of their co-administration on children’s croup. Materials and Methods In this study, all patients with croup admitted to the emergency ward of Madani Hospital Khorramabad were divided through the simple randomized method into 3 groups after informed consents were taken from their parents. The first group was given cold drink, second group with dexamethasone (DM), and the third group were given the combined treatment simultaneously. The patients in the first and second groups who did not show signs of improvement received the simultaneous treatment similar to the third group. The data were analyzed using the SPSS software through descriptive statistics and inferential statistics including multi-field variance analysis and co-variance analysis. Result The results of the study indicated a statistically significant between the 3 group in terms of improvement time-scale of croup clinical symptoms (P=0.001). There was no significant difference observed between the effects of other variables on improvement time-scale of croup clinical symptoms. Conclusion The cold drink has less treating effect than DM and combined simultaneous treatment method. Also, DM had more influence than simultaneous treatment method. In addition, other variables including age, sex, birth weight, BMI, respiratory allergy and previous croup history did not influenced improvement time-scale and only type of intervention influenced improvement time-scale of croup clinical symptoms.