These cheerful yellow and white harbingers of spring, aka daffodils and jonquils, are actually mildly toxic if the bulbs are eaten in large quantities Daffodil bulb diners tend to experience nausea, vomiting, cramps and diarrhea. A doctor might recommend intravenous hydration and/or drugs to stave off nausea and vomiting if symptoms are severe or the patient is a child.