The age of Medical Marijuana has brought on a wave of brand new strains that have been crossbred and specifically grown to treat certain ailments. Typically, these strains are lumped into one of three major categories, "Indica, Sativa or Hybrid". Indica strains of cannabis are targeted for patients seeking pain relief, sleep aid and body effects. Sativa strains are typically felt more in the head, and are utilized in treating anxiety, depression and fatigue among other things. Hybrid strains are a blended percentage indica and sativa. Education around this can ensure that the desired effects for the patient will work as intended.
Note: A small percentage of cannabis consumers will sometimes experience opposite effects then that of the general population, and may feel sleepy with sativa strains or wired awake with indica. It's very important to remember that everyone is different, and cannabis metabolizes with each individual person uniquely. It can help to keep a journal with doses and effects to keep yourself organized.