There are several side effects to consider before giving a child an antihistamine. These include:

• Drowsiness. Antihistamines can make many children sleepy. For this reason it may be a good idea to give the drug to children at bedtime.
  
  
• Hyperactivity or jitteriness. Some children react to antihistamines with varying types of restlessness. Concerned parents should contact their child’s physician to arrange for a dosage or medication change.
  
  
• Seizures. This condition is more likely to occur in children who take antihistamines than in adults. If a child experiences convulsions, parents should alert their child’s physician immediately.
  
  
• Nightmares and irritability. These symptoms may appear in varying degrees in some children. Concerned parents can consult with their child’s physician to change drugs or dosage.

Parents are encouraged to discuss their concerns about antihistamine use with their child’s physician.