SN instructed patient / caregiver regarding medication Digoxin. Explained that Digoxin helps make the heart beat stronger and with a more regular rhythm to treat A - fib. Explained that the side effects may include mild nausea, vomiting, diarrhea and headache. SN instructed patient / caregiver to avoid becoming overheated or dehydrated during exercise, in hot weather or by not drinking enough fluids, because Digoxin overdose can occur more easily if dehydrated, and to call 911 if overdose is suspected. Explained that the overdose symptoms may include severe nausea, severe vomiting or diarrhea, loss of appetite, blurred vision, seeing halos around lights or objects, severe skin rash, fast / slow or uneven heartbeats, and feeling like passing out. SN instructed patient / caregiver to notify physician ( MD ) if experiencing persistent side effects or adverse effects.