Common Side Effects

• According to the Mayo Clinic, common but not serious side effects include drowsiness, headache, lightheadedness and dry mouth.
  
  

Serious Side Effects

• Serious side effects include fluctuating heart rate, dark or cloudy urine, trembling and ringing in the ears. A patient experiencing these symptoms should consult with a physician before continuing Lortab doses.
  
  

Severe Side Effects

• According to Drugs.com, severe side effects that require immediate medical attention include convulsions, yellowing of the skin or eyes, difficulty breathing and confusion.
  
  

Existing Medical Conditions

• Before using Lortab, a patient should advise her physician of existing medical conditions such as low blood pressure, sleep apnea, curvature of the spine or alcohol dependency.
  
  

Drug Interactions

• Lortab has the potential to adversely interact with aspirin, anti-inflammatory medications, bladder or urinary medications, bronchodilators and antidepressants.