From Nature:
Newspapers in the United Kingdom have jumped on the news that patients will soon be able to purchase ‘intelligent pills’ containing sensors to monitor their medication use. Nature looks at what these pills can do. Proteus Biomedical, a company based in Redwood City, California, announced on 13 January that it would be launching a “digital health product” in the United Kingdom in collaboration with the pharmacy chain Lloydspharmacy. This product, called Helius, will include “sensor-enabled tablets” to monitor patients' medication use. Compliance with doctors’ instructions has been identified as a problem area in medicine, especially when patients are prescribed multiple drugs that may need to be taken at different times.
For the system, Proteus has designed sensors called ‘ingestible event markers’, which can be taken with pills or incorporated directly into medicines as part of the manufacturing process. In this system, the sensors will be embedded in a placebo to be taken alongside a medicine. Lloydspharmacy hopes to make the system, which will be marketed to people with chronic conditions, available from September. They are activated by stomach acid and are powered much like 'potato batteries', in which two different metals generate a current when inserted into the vegetable. Each sensor contains a tiny amount of copper and magnesium, says Thompson. “If you swallow one of these devices, you are the potato that creates a voltage, and we use that to power the device that creates the signal”. The digital signal, he adds, cannot be detected except by a device that attaches to the patient’s skin, much like a bandage. This device also monitors heart rate, respiration and temperature, showing how the patient responds to the medication. These data can then be relayed to a patient’s mobile telephone and shared with whomever the patient chooses.
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