On the one hand, we recognise them as cold-hearted capitalists whose aim is to generate profits, while actually helping people is an irrelevant side-effect.
On the other hand, we appreciate that the profit motive is what drives innovation. When it comes to running a drug company, greed is good; if Mother Teresa was in charge we would see very few new and effective drugs, and keeping them at arm's length would be like killing The Goose that Lays the Golden Drugs.
So we have to do business, and our usual point of contact is the drug rep. Good people, but we have different agendas, and over the years I've developed a few maxims for handling them.
When you sup with the devil, use a long spoon. You can learn from drug reps; for example, never marinate in cologne overnight. Also, wear shades, so as not to be blinded by their shiny shoes. Then when they ask where you are going on holiday, the drug rep never really listens to your answer. Drug reps are very friendly, but it's their job; they are paid to be your friend. If the drug is effective, this friendship can be considered a reciprocal conciliation of interests.
In any picture of any medical meeting, the good-looking ones are always the drug reps.
And I have devised a special set of maxims for that most beloved of breeds, the drug rep's manager. When shaking hands with a drug rep's manager, always smear some lubricating jelly on your hand first, and enjoy the reaction. Always sit the managers on a low seat so they have to crouch uncomfortably and look up at you, and give them a plastic seat that makes farting noises whenever they shift position.
Don't react at first, then after a while get up and say: 'Boy, getting steamy in here, ain't it?' and pointedly open a window.
It's a dirty job, but somebody's gotta do it.
Dr Farrell is a GP from County Armagh. Follow him on Twitter @drlfarrell.