Digital Pills
Smart Pills, also known as digital pills or ingestible sensors, are a growing technology in the medical field for the next generation of diagnostic tools. These devices allow physicians to collect measurements and images of internal structures within a patient’s gastrointestinal tract. There are also non-diagnostic smart pills that are designed to monitor when patients take their medication in an attempt to combat the ongoing issue of medication non-adherence. The use of smart pills also raises important ethical concerns about how they affect patients, physicians, and society.
Background
The idea of the digital pill comes as an answer to the growing problem of medication non-adherence (1). This is the growing problem of patients failing to take their medication at the right time or at all. This can be serious, especially for chronic diseases such as hypertension and diabetes where an estimated 40-50% of patients are believed to be affected by medication nonadherence (3). Nonadherence likely contributes to 100,000 preventable deaths and $100 billion dollars in preventable medical expenses each year (3). Digital pills are essentially ingestible sensors that aim to resolve this issue by allowing patients, loved ones, and medical professionals to track medication consumption (4). In 2017, the FDA approved the first digital pill, Abilify MyCite, which was developed by Otsuka Pharmaceutical Co (1). The actual drug itself is called Abilify (generic name aripiprazole) and it is used for the treatment of schizophrenia and bipolar disorder (2). The sensor, developed by Proteus Digital Health, is composed of a silicon chip with a logic circuit and the two metals magnesium and copper (2). When the pill comes into contact with solutions consisting of polar molecules (like gastric acid in the stomach) it dissolves leaving behind the silicon chip (1+2). When the chip interacts with the surrounding solution it becomes activated and is able to transmit a transient electrical signal (modulated current) to a wearable patch on the patient (2). The signal received by the patch consists of a single number that informs the patch what medication has been ingested (2). Through Bluetooth, the wearable patch can relay the information to mobile devices to a compatible app (1+2). This information, with the required patient consent, can be shared with the patient’s loved ones, caretakers, and/or physicians to make sure that the patient avoids medication non-adherence. This information can also be used by the patient’s physician to assess whether a new treatment plan needs to be implemented if the expected results are not seen.
Types of Smart Pills
Imaging Capsules
These smart pills are a type of diagnostic instrument that enables doctors to collect visual data about the structural integrity and condition of organ lining inside the different organs of the gastrointestinal (digestive) tract. A major advantage of imaging capsules is that they provide an alternative to traditional imaging techniques that use tube endoscopes which are quite invasive (5). Endoscopy instruments also tend to be large and rigid which limits access to many areas of the gastrointestinal tract and brings great discomfort to patients (5). Over the years, imaging capsules have made great progress with improved algorithms for detecting hemorrhage and lesions and enhanced video quality (5).
Commercial Products
WCE by Given Imaging Inc. (5)
PillCam SB by Given Imaging Inc. This is the first swallowable camera capsule released by Given Imaging inc. and it is used to analyze the small intestine (also called small bowel, this is where SB comes from) (5). Since the initial release in 2000, newer versions have been released with greater battery power and imaging resolution (5). The images are collected by the receiver and later examined by gastroenterologists (5).
PillCam ESO by Given Imaging Inc. This capsule is used to take images of the esophagus and there are two cameras, one at each end, to get more information in less time (5). The pill travels down the esophagus very quickly (10s of seconds) and consequently, the pill is designed to have a short battery life but a high frame rate (5).
PillCam COLON by Given Imaging Inc. A small capsule used to image the colon and these are mostly used as complements to the traditional colonoscopy procedure (5). Due to the larger size of the colon, the cameras on this capsule are equipped with wide-angle imaging (5).
Endo Capsule (Olympus Inc.)
OMOM capsule by Chongqing Jinshan Science and Technology
MiroCam capsule
