Icon WebMD Expert Blogs

Dr. Lloyd's blog has now been retired. We appreciate all the wisdom and support Dr. Lloyd has brought to the WebMD community throughout the years.

Monday, November 17, 2008

Next Millennium Drug Delivery

Drug researchers have a lot to consider when they create new medical treatments. Besides chemical formulation, bioavailability and potential adverse effects, these scientists also want to optimize the delivery of the new drug to where it is needed most.

The eye is a particular challenge because eyedrops don’t simply migrate across the clear cornea and enter the eye – although at times we wish they could! If this were the case the eye would double in size everytime we swam underwater without goggles!

A variety of biochemical barriers and microscopic membranes interfere with direct drug transport. Clever drug researchers invented eyedrop formulations that allowed the medicine to alter its identity (electrical charge, lipid and water affinity, and pH) as the compounds make their way across the cornea.

When eye specialists needed a way to deliver high doses of antiviral medication to people with CMV retinitis (a blinding eye infection) inventors created tiny drug wafers that could be surgically implanted deep inside the eyeball. Some intravenous drugs are inert until stimulated by infrared, microwave or RF energy that is externally applied to the target organ. Again, put the drug where its needed.

Other medical specialists grapple with similar challenges. Powerful drugs used to treat colon cancer or severe intestinal inflammation can make people very sick as the drug circulates throughout the bloodstream. A team at the Dutch electronics conglomerate Philips has unveiled the intelligent pill – the iPill. Think of the iPill as a robot dumptruck with a built-in cellphone. It has its own wireless transmitter and measures 1.0 by 0.5 inches (bigger than a ‘Mike & Ike’ candy) and it cannot be chewed!

Gulp! Once it is on its way the iPill broadcasts the acidity of the surrounding contents. Since acidity drops as intestinal contents travel south of the stomach this is an accurate way to map its location. I don’t think consumer-grade GPS gear is that precise yet but I’m sure NASA is already working on it.

Once the iPill is at the desired location (duodenum, ileum, acsending colon, transverse colon, descending colon) it electronically releases the perfect dose of the prescribed medication. The rest of the body is unaffected. With traditional medicines you may need to consume 500mg in order to get 50mg to reach the target organ. The rest of the body has to deal with the leftovers!

Okay, I know what you’re thinking: how much will it cost? The prototype versions run $1000 per iPill (equivalent to 4 iPods!) Over time, like all electronic gadgets, the price will drop significantly…perhaps down to $10 per swallow. In the meantime I just hope Philips does not license the technology to Apple!

Okay, okay, I know what you are really thinking: what happens to the iPill once the journey is complete? It enters the iToilet and heads for the iSewer. Folks are already concerned that there is too much excreted Prozac in our drinking water, what happens when thousands (or millions of Americans start swallowing iPills? The iPill team at Philips says they don’t have a good answer yet. For now they are still working on a solution. I’m not too worried. Having seen all of the bizarre things my children have accidentally dropped in the potty I’ve never seen them reappear from my kitchen faucet.

Related Topics:

Posted by: Bill Lloyd MD at 3:29 pm


Subscribe & Stay Informed

WebMD Daily

Get your daily dose of healthy living, diet, exercise and health news from WebMD!


WebMD Health News