In an effort to find more efficient ways of delivering drugs to the brain, Danish researchers tested a natural sugar polymer that is capable of carrying drugs through the nasal wall and into the brain, according to a study published in the International Journal of Pharmaceutics.

According to researchers, only a fraction of the amounts of drugs in a pill actually reaches the right place in the body; the rest never reaches its destination and may cause unwelcome side effects. This kind of major overdosing is especially true when doctors treat brain diseases, because the brain does not easily accept entering drugs.

“People with brain diseases are often given huge amounts of unnecessary drugs. During a long life, or if you have a chronic disease, this may become problematic for your health,” said Massimiliano Di Cagno, assistant professor at the University of Southern Denmark.

The vehicles for drug delivery through the nose are typically made of so-called polymers, according to researchers. “If the drugs cannot get out of their vehicles, they are no help to the patient. So we needed to develop a vehicle that does not lock the drug in,” Di Cagno said.

Researchers tested novel ?-cyclodextrin (?CD)-dextran polymers and reported that all investigated ?CD-polymers are of appropriate sizes for parenteral administration.

“This [research] is an important breakthrough, which will bring us closer to delivering brain drugs by nasal spray,” Di Cagno explained. “We have solved the problem of getting the drug through the nose, and we have solved the problem of getting the drug released once it has entered the brain. Now there is a third major challenge left: To secure a steady supply of drugs over a long period. This is especially important if you are a chronic patient and need drug delivery every hour or so.”

To address the challenge of gravity inside the nose cavity Di Cagno said a future step is to invent some kind of glue that will help the solution stick to the nasal wall and not run down and out of the nose within minutes.