This week health secretary Alan Johnson announced that he wasn't going to stick by the pharmaceutical price regulation scheme that lines the pockets of the drugs industry. You only have to say those words to trigger my favourite three-minute dinner party package: how evil is big pharma?

In the UK, the pharmaceutical trade is the third most profitable activity after finance and - this will surprise you if you live here - tourism. We spend £7bn a year on pharmaceutical drugs, and 80% of that goes on patented drugs - medicines released in the last 10 years. In 2002, the 10 US drug companies on the Fortune 500 list had combined international sales of $217bn (£106.6bn).

They spent only 14% of that money on research and development, but 31% on marketing and administration. They are very careful not to let anyone see how much goes on marketing and on administration. Whenever you hear the drug companies explaining why they have to charge so much for their products - perhaps as they are denying their lifesaving Aids drugs to the 20 million HIV-positive people in Africa - the plea is that they need money to develop new drugs. That's not true if they spend twice as much on marketing as on research and development. This unhappy collision of facts makes them look very evil indeed.

They also charge this money in slightly evil ways. Drugs have 10 years "on patent." Loratadine is an effective antihistamine drug that does not cause drowsiness. Before the patent ran out, the price of this drug, by Schering-Plough, was raised 13 times in the US in just five years, increasing by over 50%. This is not a price rise in keeping with inflation. This is evil.

But it's also an industry in trouble. The golden age of medicine has creaked to a halt, and the number of new drugs being registered has dwindled from 50 a year in the 1990s to about 20 now. At the same time, the number of "me-too" drugs has risen, making up to half of all new drugs.

Me-too drugs are an inevitable function of research driven by a market: they are rough copies of drugs made by another company, but they are different enough for a manufacturer to claim its own patent.

They need to be tested and marketed just like a new drug; but for all that effort they generally don't represent a significant breakthrough in human health. They are merely a breakthrough in making money. Again, you have to admit, that is reasonably evil.

But what really interests me is what we do with our feelings about this evil, market-driven venality, which can be found in every market sector. But we find it uniquely distressing when we are sick and needing healthcare.

This moral discomfort and resentment leaks out in delusional anti-MMR beliefs, or bizarre acts of faith in the vitamin pill industry, as acts of misguided and wasteful political rebellion. Why? Because everybody is a socialist when it comes to healthcare, but nobody knows what to do with those feelings any more.

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