Washington, April 14 (IANS) An injectable gel could ease the crippling joint pains that a large number of rheumatoid arthritis and osteoarthritis patients suffer from.

"We think this platform could be useful for multiple medical applications, including the localised treatment of cancer...and cardiovascular disease," said Jeffrey Karp. His research team developed the potentially new way to treat these two conditions at Brigham and Women's Hospital.

Arthritis is a good example of a disease that attacks specific parts of the body. Conventional treatments for it, however, largely involve drugs taken orally, reports the Journal of Biomedical Materials Research: Part A.

Not only do these take weeks to exert their effects, they can have additional side effects. That is because the drug is dispersed throughout the body, not just at the affected joint, according to a Brigham statement.

Further, high concentrations of the drug are necessary to deliver enough to the affected joint, which runs the risk of toxicity.

"There are many instances where we would like to deliver drugs to a specific location, but it's very challenging to do so without encountering major barriers," says Karp.

For example, you could inject a drug into the target area, but it won't last long - only minutes to hours - because it is removed by the body's highly efficient lymphatic system.

What about implantable drug-delivery devices? Most of these are composed of stiff materials that in a dynamic environment like a joint can rub and cause inflammation on their own.

Further, most of these devices release medicine continuously, even when it's not needed. Arthritis, for example, occurs in cycles characterised by flare-ups, then remission.

"The Holy Grail of drug delivery is an autonomous system that (meters) the amount of drug released in response to a biological stimulus, ensuring that the drug is released only when needed at a therapeutically relevant concentration," Karp wrote.