A La Pharmacie…

A pharmacy visit in France is slightly different to one in England. It is often more akin to a doctor visit as they are able to hand over medications that, in the UK, would require a doctor’s prescription. I have friends who tell me that they stock up with medications whenever they visit France so that they can dish them out to their families back in Blighty without the need to visit a doctor. I am not sure how good an idea this is!

With medications such as antibiotics (for treating bacterial infections), it is important to consider the dose response. In other words, the strength of the medication affects the outcome of the treatment. This is the same with poisons. Take the lethal poison ethanol as an example (the type of alcohol found in wine). You might wonder why, if it is a lethal poison, it is safe to drink it in a glass of wine. The lethal dose for ethanol is about 6 g of ethanol per kilogram of body mass so for a 60 kg adult, about 360 g of ethanol is enough to kill them. This is equivalent to drinking about 1 litre of whiskey or four bottles of wine. Your liver is constantly breaking down the alcohol so if consumption takes place over a long enough period of time, a lethal level of ethanol will (probably) not be produced. In children, the lethal dose is about half that for an adult.

With antibiotics, your doctor will give you medicine of a specific strength and a course that lasts a particular length of time. As you start to take the pills a level of antibiotics will build up in your system and start to attack the bacteria which are susceptible to it. By taking the pills at regular intervals you can maintain a level dose of the antibiotic within your system.

This gives the bacteria less chance to escape the antibiotics. About 60% of the way through the treatment (or maybe sooner) you will start to feel the symptoms going away. It is tempting at this point to stop taking the medicine but it is a very bad idea not to complete the course. You may have reduced the population of infectious organisms enough to relieve the symptoms but you will possibly not have killed the maximum number of bacteria possible. If you stop the antibiotics too soon you will leave some bacteria behind in a low concentration of the antibiotic and they may develop a resistance to the medicine. This is one of the ways in which antibiotic-resistant bacteria can be produced. Always finish the full run of the prescription to make sure that you kill as high a proportion of the bacteria within your body as possible.

One of the quirks of the French system is that as well as selling you lots of lovely strong medicines in the pharmacy, they are also very likely to load you up with alternative treatments such as homeopathic remedies.

Any treatment that can be shown to work is called medicine. Any treatment that cannot be shown to work, or that has been shown not to work, is called alternative medicine.

I have written about homeopathy on here several times but the principle is interesting. It is based on two simple ideas. Firstly the notion that a chemical that causes a symptom can be used as a treatment for a condition that produces the same symptom. An example of this would be coffee. Caffeine famously keeps people awake so if you are treating someone who is having trouble sleeping you could use coffee in their remedy (coffea). Another example is onion. Onion causes your eyes to water so if you want to treat a cold, which has the common symptom of watery eyes, you would use a therapy derived from onions (alium cepa). A homeopathy practitioner will tell you that it is more subtle than this but it is essentially a process of matching the treatment to the symptoms

The second principle of homeopathy is that the more dilute the medicine is, the stronger its effect will be. To this end, the active ingredient is diluted by a factor of 10 or 100 several times, with each dilution being accompanied with some vigorous shaking (known as succussion). The dilution happens to such an extent that it is highly likely that there is no caffeine in a homeopathic insomnia medicine and no onion in a homeopathic cold remedy. They are just sugar pills, or watery sprays, with absolutely no scientific way of distinguishing one from the other. This makes them quite safe, of course, as there is no chance of being poisoned by a homeopathic remedy. This is just as well as the deadly poisons belladonna (deadly nightshade) and arsenic are both popular remedies too (each listed as possible treatments for both colds and insomnia incidentally). You may have used arnica (a highly toxic plant) cream to treat bruises. It is usually a homeopathic remedy but sometimes will contain very faint traces of arnica at which point it would probably be better called a herbal remedy. Either way, it is highly unlikely that the arnica is having an effect upon the bruising or the pain.

All of this is just harmless fun until people with serious, treatable diseases rely upon alternative medicines instead of seeking the best available medical help. An organisation called Homeopaths Without Borders went out to Haiti after the earthquakes in 2010 to treat the victims with homeopathy. They were soon followed by, no doubt well-meaning, acupuncturists and meridian tappers when what was needed was field hospitals, money and genuine help. Some unscrupulous homeopaths also offer to treat malaria. Malaria is a disease that disproportionately affects poorer parts of the world. According to the World Health Organisation, there were 212 million cases of malaria in 2015 resulting in 429,000 deaths. The disease is spread by the Anopheles mosquito and caused by 5 protist species, most notably Plasmodium falciparum and Plasmodium vivax. I am going to go out on a limb here and say that malaria cannot be cured with sugar pills that have had pure water sprinkled on them.

Please read the other posts in the homeopathy series if you are interested. Dilution Dilemma goes into the mathematics behind the dilutions and Why Science Lessons Are Important features an eight-minute video by Dr Werner explaining “how homeopathy works”. I have recently updated the article with some questions at the end. For now, I will leave you with the Mitchell and Webb Homeopathic A&E sketch from their TV series. One of my favourite bits of scientific satire!

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Below is a longer video, with fewer gags, but by one of my heroes Richard Dawkins. Don’t feel that it is essential viewing but I put it here for the sake of completeness. He is a real scientist who brings his understanding of evidence to the topic whilst remaining quite generous to the people he interviews.

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Questions…

1. Name a condition caused by a bacterium. What are its major symptoms?
2. What sort of organism causes the common cold?
3. What is the chemical formula of ethanol?
4. Name a human organ other than the liver and briefly describe its main function.
5. Which poisonous non-metal element is mentioned in the passage above?
6. What characteristic distinguishes protista from bacteria?
7. [Harder] What process occurring in bacteria allows them to develop antibiotic resistance?