Problem: A patient with congestive heart failure and six weeks status post-acute MI had been prescribed and was correctly taking Lanoxin (digoxin). She began to experience nausea and vomiting with extreme fatigue. She was admitted to the hospital. Blood drug levels are taken and it is determined the patient is experiencing a side effect of the medication. A different medication is prescribed for her heart disease to avoid these symptoms. The patient's cardiac conditions are evaluated and found to be stable.