Clinical presentation

The clinical effects of poisoning due to various less-sedating antihistamines are similar. Effects include:

• central nervous system effects
  • mild sedation
  • anticholinergic effects (rare)
  • seizures (rare)
  • acute dystonias in children (rare)
• cardiovascular effects, especially in patients with cardiac disease
  • tachycardia, mild postural hypotension (common)
  • arrhythmias, QT-interval prolongation and torsades de pointes with loratidine (rare).