553f5c59_cyclopedia___Kaiser_Permanente_n_medicines_that_are_monitored_Tests_you_may_have
[Examples] Digoxin [What they do] It helps control heart rate and helps make your heart beat stronger. [Why monitor them] When you start taking this medicine,you may need to have frequentblood tests to monitor the levelof the medicine in your body. If your kidneys aren't working properly, the medicine can build up to a dangerous level. Also, the level of potassium in your body may affect how the medicine works. [How often] At least once a year or as often as your doctor suggests [Tests you may have] 
Blood test to check the drug level in your blood Potassium (K) in blood Creatinine or blood urea nitrogen
Health-Encyclopedia - Kaiser Permanente