A.C. is a 60-year-old Caucasian woman with newly diagnosed peptic ulcer disease, generalized anxiety disorder, and iron deficiency anemia. She also has a long history of asthma and depression. She is a strong believer of herbal medicine. She takes St. John’s wort for her depression, iron pills for her anemia, and alprazolam (Xanax) as needed for her anxiety. During her asthma exacerbation, she is instructed to take prednisone for at least 5 days. She also takes esomeprazole (Nexium) for her peptic ulcer disease. Three months later, she experienced severe fatigue, shortness of breath, dizziness, and swelling/soreness in the tongue. Her asthma is well controlled with the occasional use of albuterol (Proventil) inhaler. During her physical exam, her physician suspected that she had bacterial vaginosis and gave her a prescription for a 1-week course of metronidazole (Flagyl). She drinks at least two to three cans of beer per day.
Review the above case and post a discussion that evaluates the potential for interactions that may increase drug availability. What is the cause of increased drug availability? Evaluate for interactions that will decrease drug availability. What is the cause of decreased drug availability? What recommendations may be made concerning the co-administration of these medications?