As far as I know the Pharmacoeconomics is a sub-discipline of health economics, and it deals with cost benefit and cost effective analysis. I hope this helps
Pharmacoeconomics is a subdiscipline of the health economics but the main difference is pharmacoeconomics evaluates the cost and efects of pharmaceutical drugs or drug therapies. Health economics is broader (is not limited only to drugs but for example diagnostic strategies, nonpharmacological therapy - such as surgery, prevention models and so on.)
Health economics is one of the specialities within economics just like environmental economics, monetary economics, public economics and development economics. Health economic research is largely based on microeconomic theory and econometrics, and topics in health economics such as economic evaluation of healthcare interventions have strong theoretical underpinnings in microeconomics. Pharmacoeconomics is a term mainly used by pharmacists and those with a medical background to refer to economic evaluation in the context of pharmaceutical interventions. It is not a branch or subdiscipline of health economics in the strict sense.
Pharmacoeconomics is a subdiscipline of the health economics but the main difference is Pharmacoeconomics evaluates the cost and effects of pharmaceutical drugs or drug therapies. Health economics is broader (is not limited only to drugs but for example diagnostic strategies, nonpharmacological therapy - such as surgery, prevention models and so on.) which I want to recommend.
The fact that 'pharmacoeconomics' evaluates the costs and effects of pharmaceutical drugs does not make it a sub-discipline of health economics. It is merely a coined term by pharmacists and/or other health scientists who do not understand that 'pharmacoeconomics' can't be a sub-discipline of health economics since health economics is in fact not a distinct field but a sub-discipline of economics. If we are to use that logic, then one could further come up with subdisciplines of 'pharmacoeconomics' which would then become cyclical, inaccurate, laughable and misleading. Think of another field, say transport economics. Do you hear economists talk of sub-disciplines of transport economics?