Use of sodium polystyrene sulfonate for hyperkalemia

Let's start with a patient case.  A 58 year old male is sent to the hospital from his PMD for hyperkalemia.  He has a past medical history of diabetes mellitus type 2, hypertension, osteoarthritis, and obesity for which he is taking sitagliptin 100 mg daily, lisinopril 20 mg daily, atorvastatin 80 mg daily, and aspirin 81 mg daily.  Pertinent findings on arrival to the emergency department are SCr = 1.2 mg/dL (at his baseline), K+ = 5.9 mEq/L (previously 4.2), blood pressure = 152/96 mm Hg, Hb A1c = 10.8%, and a normal EKG.  Upon further questioning about his medication and supplement use, he admits to occasional ibuprofen and oxycodone use this past month for his osteoarthritis and is newly using Morton's Salt Substitute (as he's trying to avoid salt because of his uncontrolled hypertension).  What is the role of sodium polystyrene sulfonate (SPS) in this situation?

Risk of peripheral neuropathy with fluoroquinolones

Last year, the FDA issued a drug safety communication, warning about the risk of nerve damage from fluoroquinolone antibiotics.  You can read last year's post about the warning and other information on fluoroquinolones here: Serious peripheral neuropathy and fluoroquinolones.  

The questionable role of digoxin in atrial fibrillation

Let's start with a patient case.  An elderly patient is admitted to the hospital with complaints of intermittent shortness of breath and a fluttering feeling in his chest.  He has a past medical history of hypertension, atrial fibrillation, and heart failure (EF 6 months ago = 30%).  He is currently taking ramipril 10 mg daily, metoprolol succinate 50 mg daily, and warfarin 6 mg M/W/F and 3 mg the rest of the week.  Other findings include a BP of 106/56 mm Hg, a creatinine clearnace of 40 mL/minute, an INR of 1.28, and atrial fibrillation with a heart rate in the 80s but a rapid ventricular response intermittently into the 120s bpm.  What should be recommended at this time to control this patient's atrial fibrillation and what is the role of digoxin, if any?