Objective: To determine whether vomiting after mild head injury in chi
ldren is related to migraine and to identify predictors of vomiting af
ter head injury.Methods: A series of consecutive children admitted to
the observation unit of an emergency department after mild head injury
was identified by chart review. A telephone interview with the parent
s or child or both was then conducted by using a structured questionna
ire. Results: Of 47 eligible children with acute head injury, 44 (94%)
were contacted. The mean age at head injury was 7.4 years. Twenty-nin
e children (66%) vomited after the head injury, The likelihood of vomi
ting was increased if the child had a history of recurrent headache (p
= 0.05). If the headaches were migrainous, the likelihood of vomiting
increased further (p <0.002). All 15 children with a history of motio
n sickness vomited after the head injury. Family history of migraine,
particularly maternal (n = 21), also predicted recurrent vomiting (p <
0.001). If more than one of these predictive variables was present, th
e likelihood of vomiting was 100%. Conclusions: History of motion sick
ness, migraine headaches, and family history of migraine are highly pr
edictive of vomiting after a mild head injury.