text: Blurred vision, xerostomia, dry nasal passages, dilated pupils, constipation, and urinary retention. (due to its anti-cholinergic effects)
  Chest discomfort/pressure (In children less than 2 years old)
  Akathisia
  Less frequent:
  Cardiovascular side effects to include arrhythmias and hypotension
  Neuroleptic malignant syndrome
  Liver damage and cholestatic jaundice
  Bone marrow suppression, potentially resulting in agranulocytosis, thrombocytopenia, and leukopenia
  Depression of the thermoregulatory mechanism resulting in hypothermia/hyperthermia
  Rare side effects include:
  Seizures
  Because of potential for more severe side effects, this drug is on the list to avoid in the elderly.  In many countries (including the US and UK), promethazine is contraindicated in children less than two years of age, and strongly cautioned against in children between two and six, due to problems with respiratory depression and sleep apnea.
  Promethazine is listed as one of the drugs of highest anticholinergic activity in a study of anticholinergenic burden, including long-term cognitive impairment.
  Overdose
  Promethazine in overdose can produce signs and symptoms including CNS depression, hypotension, respiratory depression, unconsciousness, and sudden death. Other reactions may include hyperreflexia, hypertonia, ataxia, athetosis, and extensor-plantar reflexes. Atypically and/or rarely, stimulation, convulsions, hyperexcitability, and nightmares may occur. Anticholinergic effects like dry mouth, dilated pupils, flushing, gastrointestinal symptoms, and delirium may occur as well. Treatment of overdose is supportive and based on symptoms.