Pontifications on Poison
Being some ramblings on events associated with poisonous plants.
Friday 20th January 2012
My ‘Lethal Lovelies’ talk is divided into sections so as to allow the audience to see progress and, as I always say, have an idea of how much longer they need to try and stay awake. The final section is headed ‘The Phantastica’ and, unsurprisingly, deals with the psychoactive plants.
There is usually a reaction when the first plant that appears is Camellia sinensis, the tea plant. Not everyone realises that tea contains caffeine and, even if they do, people don’t immediately think of caffeine as in the same category as, say, marijuana or alcohol.
Coffea arabica, coffee
Picture by J M Hullot
The relative importance of tea and coffee, obtained from a number of species in the genus Coffea though Coffea Arabica is the best known, leads to one of those questions that has no correct answer. If asked ‘which has more caffeine, coffee or tea?’ the more correct answer would be ‘tea’, however, if the question is posed as ‘which has more caffeine, a cup of tea or a cup of coffee?’ then the answer becomes ‘coffee’.
Sudden withdrawal of caffeine results in a variety of symptoms such as dizziness, headaches, constipation, indigestion, palpitations and insomnia but most people never experience these because they maintain a similar intake of caffeine and don’t make any sudden changes in consumption. The exception to that is where someone consumes more tea or coffee during the working week and then suffers withdrawal at the weekend. In those cases, the symptoms may be so slight as to not invite investigation and people think that feeling better on their return to work is just that they have something to ‘take their mind off’ the slight headache or stomach discomfort that took the edge off Sunday.
More recently, however, there has been an additional source of caffeine, aimed particularly at the active young, and that is the so-called energy drinks. Now, a paper from Australia has looked at the problems arising from excessive consumption of such drinks.
It is important to get some context. The paper looked at the 297 calls to the New South Wales Poison Information Centre (NSWPIC) from 2004 to 2010. The NSWPIC gets around 110,000 calls per year so the 297 related to energy drinks is from around three-quarters of a million calls. The authors, however, point out that the concern is the growth in the number of these calls. There were 12 calls in 2004 but this had risen to 65 by 2010.
Analysis of the calls received, suggested that energy drinks are often used as mixers with alcohol and that may worsen the symptoms, however, of the 128 people who needed to attend a hospital emergency room, 57 had not had any other substance that could have contributed to their symptoms. Though no figure seems to have been given, the authors say that some of the cases reported drinking within the manufacturers’ recommended consumption.
The caffeine content of energy drinks varies from brand to brand and, say the authors, this makes it hard to know exactly how much caffeine the consumer is having. They also note that one of the constituents of energy drinks is guarana, an extract from the plant Paullinia cupana. This plant is also a source of caffeine but not every manufacturer includes the caffeine from guarana in its labelling of caffeine content.
The authors conclude by calling for improved labelling to make caffeine content clearer and suggest that controls on the strength of these drinks may be required. They also say more needs to be done to make consumers aware of the risks from mixing energy drinks and alcohol and the danger if other stimulant substances, such as caffeine pills or amphetamines, are consumed at the same time.
It almost seems as though we are going along the same road that saw people go from the generally harmless practice of chewing coca leaves, from Erythroxylum coca, to using the extracted alkaloid, cocaine, and, of course, the call for khat to be banned could, I have argued, result in the alkaloids of Catha edulis becoming available to the general population.
As news of this research spreads, I shall look forward to a variety of harrumphing opinion pieces calling for drinks containing caffeine to be classified under the Misuse of Drugs Act.