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We recently reported on how acetaminophen can slow bone growth. Now, researchers in the US are warning that consuming large amounts of caffeine while taking acetaminophen, the widely used painkiller, could potentially cause liver damage. The combination of painkiller and caffeine is a well-known “morning-after-the-night-before” concoction and is often used to deal with an alcohol hangover, which presumably could compound the potential liver damage still further.

A preliminary laboratory study published in the October 15 issue of Chemical Research in Toxicology explains how this toxic interaction might arise not only through drinking coffee and beverages with added caffeine while taking the painkiller but also from using large quantities of medications that combine caffeine and acetaminophen for the treatment of migraine headaches, menstrual discomfort and other conditions. The preliminary bit of this research refers to the fact that it’s only been demonstrated in bacteria engineered to express the appropriate liver enzymes, though.

Of course, health experts have warned for many years that excess alcohol coupled with acetaminophen could cause liver damage and in the worst-case scenario even death. This is the first time that a potentially harmful interaction with the painkiller and caffeine has been reported, and even if it has only been demonstrated to harmful to bacteria you might err on the side of caution and go cafe lite next time you’re popping those pills to quench a hangover.

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Years ago, I wrote about the lab-on-a-CD concept (actually it was in the September 2001 issue of Reactive Reports). Now, it seems the use of CD-ROMs and DVDs and the hardware used to play these popular audio and video compact discs (CDs) is coming of age in terms of home health monitoring and laboratory-based testing. Scientists in Spain say CD technology could be adapted for tests ranging from the measurement of environmental toxins to at-home disease diagnosis.

Angel Maquieira and colleagues at Valencia Polytechnic University have developed a CD with an immunoassay surface coating that can detect three pesticides, 2,4,5-TP, chlorpyrifos, and metolachlor, when samples are placed on the disc. By spinning the disc in a CD player the standard laser light can “read” the chemistry of the bound pesticides and a computer interpret the changes in laser intensity to identify them.

“The obtained results show the enormous prospective of compact discs in combination with CD players for multiresidue and drug discovery applications,” the researchers say. They are now improving sensitivity and versatility.

More information in the journal Analytical Chemistry

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Many years ago, I reported on the earliest synthesis of the analgesic compound epibatidine from the poison frog Epipedobates tricolor. You’ll notice I was careful to say poison frog, not poison dart frog. In the prestigious pages of Science in 1993 I wasn’t quite so careful and describes this creature as a poison dart frog.

It was a simple mistake to make as there were dozens of references in the literature to this species as the toxic secretions of this and other frogs as being used in poison darts. However for E tricolor, this wasn’t and isn’t the case. It’s a toxic frog most certainly, but no one has ever tipped their darts with its secretions. The venom in the deluge of letters from readers wishing to highlight and correct my error while I was still a cub reporter writing freelance for the journal via its Cambridge office was enough to make my toes curl.

Anyway, the analgesic properties of epibatidine became famous. Several hundred times more potent than morphine, but with none of the addictive properties of its fellow opiates, it seemed that its career as a new painkiller was set. It has, as you can see from the picture, a quite stupendous chemical structure, which took several attempts to yield a total synthesis. Efforts are still ongoing I see from a quick scan of the current literature. A paper in JOC this month, has Armstrong, Bhonoah, and Shanahan wrestling with an aza-prins-pinacol approach to the 7-azabicyclo[2.2.1]heptanes of which epibatidine and its close cousin epiboxidine are examples.

It still surprises me that so little work seems to have been done to bring this compound and its analogs into the pharmaceutical fold. For instance, only a limited number of analogs have actually been synthesized and evaluated in vitro and negligible numbers have been tested in vivo. Given the enormous market a non-addictive painkiller with opiate-like power might share, I wonder why. Any pharma readers care to enlighten us?

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