Key:
	AD   = antidepressants
	ACEi    = ACE inhibitors (a class of drugs which lower blood pressure)
	AED   = antiepileptic drugs (anticonvulsants)
	benzos   = benzodiazepines (e.g., diazepam, clonazepam, alprazolam)
	In terms of U.S. prescription volumes in 2009, lipid lowering drugs
	(e.g., statins) and codeine or codeine combinations (synthetic painkillers) were the dominant drugs.
	Interestingly, three families of neuropsychiatric medications were commonly prescribed.  Antidepressants were the third most dominant drug class in terms of # of prescriptions dispensed (168.7 million prescriptions).  AED (anti-epileptic drugs, which are used not only for seizure disorders, but increasingly for control of mood swings, aggression, and misbehavior) placed seventh (104.5 million prescriptions).  Benzodiazepines (so-called “minor tranquilizers” or anti-anxiety drugs) finished eleventh.