There are various sampling methods. The one chosen will depend on a number of factors (such as time, money etc.). 1. Random Sampling Everyone in the entire target population has an equal chance of being selected. This is similar to the national lottery.
Various types of medications have been evaluated for migraine prophylaxis, including beta blockers, antidepressants, anticonvulsants, nonsteroidal anti-inflammatory drugs (NSAIDs), angiotensin blockade agents, and calcium channel blockers.
If migraine pain is very severe and does not respond to other drugs, doctors may try painkillers containing opioids. Opioid drugs include morphine, codeine, meperidine (Demerol, generic), and oxycodone (Oxycontin)]. Butorphanol is an opioid in nasal spray form that may be useful as a rescue treatment when others fail.