The Nurse Is Caring for a Client Who Has Been

The nurse is caring for a client who has been diagnosed with migraine headaches that occur every 2-3 days and placed on preventive therapy with the beta blocker propranolol (Inderal) .Which data indicates the medication is effective?

A) The client has supplemented propranolol with sumatriptan (Imitrex) four times this week.
B) The apical pulse is 78 beats per minute for this client.
C) The client had only one headache in the past week.
D) The client has developed orthostatic hypotension.