Philips plans computer in a pill

The iPill is about the size of a large multivitamin tablet

Philips is conducting trials of a tiny computer that takes the form of a pill that can be swallowed. The device will dispense medicines, and can be controlled within the human body.

The iPill (intelligent pill) is designed to release medicine in controlled bursts inside the body at the command of a doctor communicating wirelessly with the device.

"If a doctor sees an adverse reaction, a signal could be sent to override the iPill and not distribute any more of the drug," Steve Klink, a senior communications manager at Philips Research, told The New York Times.

The pill is about the size of a large multivitamin tablet, and is designed to pass out of the body within 24 hours. A wireless antenna controls a pump inside the pill, so that medicine can be dispensed either in small doses or all at once.

The pump is a screw-driven piston powered by an internal silver-oxide battery, which has enough power to last for 48 hours.

The iPill is currently being tested in animals, but human volunteers have taken it to make sure the device can pass easily through the body.

Additional sensors can be bolted onto the iPill so that it could detect excess acidity in the stomach, for example, and dispense chemicals to restore the natural PH balance.