Wednesday, April 14, 2010

The great Phenacetin folly

Phenacetin was once a widely used pain-relieving drug that was particularly good at relieving rheumatoid arthritis (joint pain caused by an autoimmune reaction). It was once widely used as one of the drugs in APCs (compounds of aspirin, phenacetin and caffeine) but it is now banned from most applications -- for very dubious reasons.

There is NO double-blind evidence that I can find showing that phenacetin is harmful in humans -- but there is certainly strong epidemiological evidence that heavy use over very long periods does do some harm to a small minority of people -- causing kidney failure in extreme cases. So it has been banned from most pharmaceutical use and is no longer available in "over the counter" (OTC) medications such as APCs.

It is however an excellent analgesic (pain reliever) and antpyretic (it reduces temperatures when you have a fever). It is also now in some parts of the world widely used as an illegal drug as part of street cocaine!

The definitive study of the evils of phenacetin appears to be this one. It is a 20 year follow-up of 1244 women, half of whom were regular phenacetin users and half of whom were not. Keep that "20 year" figure in mind. At the end of the period 12% of the phenacetin users had died, versus 4% of the control group. The logic then is that phenacetin killed 8% of its regular users over a 20 year period

It is however flawed logic. The study was epidemiological, not experimental. So why were the women regularly taking phenacetin in the first place? Obviously because they had a lot of aches and pains. So is it at all surprising that, over a 20 year period, women with lots of aches and pains were 8% more likely to die than women who did not have lots of aches and pains?

Among the 74 phenacetin users who died, however, there was an exceptionally high incidence of kidney disease so the reasonable assumption was made that phenacetin did that. But wait a minute there too: The comparative incidence of kidney disease among users was much higher than the incidence of death! What does that mean? It would seem to mean that, although phenacetin was bad for the kidneys in a small minority of women, it also had some health-protective effects elsewhere. It was very bad for the kidneys of some women but good for preventing other causes of death.

With such evidence in mind, the normal, logical course of action would be to allow continued use of phenacetin but periodically monitor its effect on the kidneys of those using it. Its damaging effect on the kidneys is obviously so slight in normal usage that it develops only over long periods so annual (say) testing should provide a sufficient warning to the minority whom it might be harming. Instead of such a rational approach, however, phenacetin has been banned outright in most countries.

Let us compare that logic with the logic governing the use of another class of painkillers -- NSAIDS such as Naproxen -- sold over the counter in the USA as Aleve and in the UK as Feminax. I won't bore you with the very long list of names under which NSAIDS are sold, but, whatever you are using, you should look it up -- as we shall see: NSAIDS can give you acute kidney failure within 30 days of taking it. Forget 20 years, think 30 days! So which would you rather be taking? Phenacetin or NSAIDS?

I will leave that question hanging in the air as mute testimony to the insanity of modern medical regulations. Bring back phenacetin!

But wait! There's more (as the steak knife salesmen used to say)! As I pointed out, the evidence mentioned above is epidemiological and, as such, is heavily reliant on inferences and assumptions ("guesswork", to be blunt). What about direct experimental evidence? Remember the role of phenacetin in APCs as I leave you with this little gem from 1967:
"Dr. Laurence F. Prescott, who was doing clinical investigation at Johns Hopkins University, tested four ingredients in widely used analgesics, alone and in combination. He reported in The Lancet that healthy volunteers who took ten aspirin tablets a day began to excrete damaged kidney cells, reflecting at least temporary kidney injury. Surprisingly, this effect was less marked with APCs. It was also less conspicuous when he tested phenacetin alone, and still less so with medicinal caffeine. Dr. Prescott's conclusion: phenacetin alone is not the primary villain in analgesic kidney damage."

NOTE: This article is a follow-up to my recent article on the heavy use of Bex APC in Australia. And I may have more to say yet. The deeper I get into the evidence on this, the worse it looks.

I would attempt to draw all this to the attention of the FDA but I know better than to waste my time banging my head on the defensive brick wall of a vast bureaucracy -- all the more so now that President Obama has appointed two highly politicized people to run the agency.

Official British food advice for schools does a big turnaround

But some myths remain, of course -- such as the evils of salt. Salt deficiency is in fact far more dangerous than salty snacks

Toddlers are being fed too much fruit and insufficient carbohydrate to maintain their energy levels, according to a survey of English nursery schools.

Children are also given too much salty food, and the size of portions varies: some are big enough for 10-year-olds and others so small that they lack key nutrients. Parents are also blamed for putting pressure on staff to ban key sources of nourishment such as whole-fat milk and red meat.

The findings are released today by the Local Authority Co-ordinators of Regulatory Services (LACORS) which asked trading standards officers in 29 councils, including Cumbria, Hampshire and Leicestershire, to check on the lunches and snacks offered by 118 nurseries over a five-day period.

The results provide a nationwide snapshot of the food offered to more than 600,000 children who spend up to ten hours a day at nursery.

One surprise is the lack of food in mid-morning and the afternoon. Some children received only half an apple or pear to keep them going until lunch. In the afternoon some were not offered a snack at all, and for those that were, it was often banana pieces or grapes.

There was no evidence of children starving and most nurseries tried to offer a good diet. However, too many meals were based on ham, sausages and other processed meat. Overuse of packet mixes for gravy and other sauces were blamed for the high salt content of meals.

Some nursery schools were also criticised for serving too much bread, and others for excessive use of cheese, which can be high in salt. Too many lunch plates were also short of green vegetables, pulses, eggs, oily fish and red meat, which are good sources of iron, zinc and calcium for a child.

Council chiefs now want guidance for nurseries, childminders and parents on suitable food.

Paul Bettison, LACORS chairman, said: “Most people assume it’s all about beating obesity, but nutrition problems can also be caused by not giving children enough of the types of food they need. For many adults, drinking skimmed milk, eating no red meat and loads of fruit is wonderful, but it’s not what a growing body needs.”

Most nursery schools were independent, he said, and if parents were unhappy, they would move their children.

“Nurseries have a dilemma — do they do what they know is right or do they do what parents think is right? A diet for mum and dad is not the diet for a three-year-old. Parents need to be taught what is best for their children.”

Helen Crawley, of City University, London, is director of the Caroline Walker Trust, which promotes good diet. She said: “This highlights the need for new guidance for under-5s. But it depends on each child, how long they spend in a nursery and what they eat at home. I am part of an advisory group to make recommendations to the Government by the summer.”

The Basingstoke College of Technology nursery was giving children insufficient carbohydrate but has changed its snacks to fruit or carrot sticks plus crackers, bread sticks, toast, oatcakes, scones, flapjacks, cheese cubes, houmus or fromage frais.


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