Nausea and vomiting are burdensome side effects of chemotherapy. Vomiting is observed in up to 60% of treated children. An appropriate and effective antiemetic regimen has the potential to eradicate or reduce the symptoms. Differences in local guidelines characterise the antiemetic treatment across the four Danish paediatric oncology departments because the overall knowledge of the most effective antiemetics is incomplete. There is an unmet need for research, which can promote evidence-based guidelines. The impact of host genome polymorphisms should be included in the research.