Symptoms of overdose can be similar to the medication’s side effects, but are usually more severe. Patients exhibiting any of these signs and symptoms of overdose should contact their physician immediately:

• Marked sedation
  
  
• Reduced mental alertness
  
  
• Palpitations (an awareness of a strong, fast, irregular, abnormal or "galloping" heartbeat)
  
  
• Apnea
  
  
• Cardiovascular collapse (a sudden loss of adequate blood flow to body tissues)
  
  
• Hallucinations
  
  
• Tremors
  
  
• Seizures
  
  
• Dry mouth
  
  
• Flushed skin
  
  
• Fixed, dilated pupils
  
  
• Extreme tiredness
  
  
• Sweating
  
  
• Dizziness
  
  
• Slow heartbeat
  
  
• Difficulty breathing
  
  
• Fluid retention