P.T. is a 35 - year - old male with a three - year history of cluster headache . He presents to the neurology clinic for follow - up . He states that he has not had any headaches for approxi mately one year until they returned about six weeks ago . He has recently been through a divorce , lost his mother to cancer , and started a new job . His typical headache " comes out of nowhere " and reaches peak intensity within 10 minutes . The pain is very severe ( 9 on a pain scale of 1-10 ) , non - throbbing in nature , and is always located on the left side of the head above the eye . In addition , pain extends over into the temple and down into the left cheek . There is always a " runny nose " and a " runny eye " associated with the headaches . Episodes of head pain usually last about 2½ hours , and he has been getting two headaches each day for the last five days . Headaches have been occurring at approximately 9 AM and 9 PM daily . Neither acetaminophen nor ibuprofen is very effective in relieving pain . There are no " flash ing lights , " sparks , or zig - zags of light associated with the head pain . There has been an occa sional bout of nausea but no vomiting .

1. What is the difference between a sign and a symptom ?

2. What are the patient's symptoms ?

3 . What is the significance of the patient denying " flashing lights , sparks , or zig - zags of light associated with head pain " ?

4 . What does the term prophylactic mean ?