Before a doctor can prescribe medication, he or she must understand well the patient's condition, as well as know any other medicine the patient may be taking in order to avoid potentially perilous complications or drug interactions. A doctor must also ensure patient is advised of possible risks so he or she is able to make an informed decision.
When a doctor does not abide by this duty to inform the patient of a possible risk, side effect or dangerous drug interaction, it is the doctor who is liable for any injuries or illnesses that result. A doctor may also be liable for prescribing the wrong medication, the wrong dosage or medications that should not be mixed with the patient's existing prescriptions.
In the recent South Carolina Court of Appeals case of Rickerson v.Karl, patient alleged he was severely sickened after a doctor prescribed medication to him that negatively interacted with medication he was already taking and which had been prescribed to him by other physicians.