Elderly patients with advanced dementia are seven times more likely to receive antibiotics in their last two weeks of life, a Harvard study reports. Though there is little evidence that the drugs relieve suffering of such patients or increase their life span, the study says that excessive use of the drugs can contribute to the development of microbes resistant to antibiotics, a public-health hazard common in nursing homes.

Researchers from Harvard Medical School studied more than 214 patients with an average age of 85 in 21 Boston-area nursing homes. Almost half died during the 18-month study that time. These patients also failed to recognize loved ones, sized to communicate and were unable to walk or feed themselves.

Two-thirds of the patients received at least one course of antibiotics during the study period, with an average of four courses being given, the author found.

Study lead author Dr. Erika D'Agata, an assistant professor of medicine at Harvard Medical School said, "Antibiotic exposure is extensive in nursing home residents with advanced dementia, and it increases as patients near death."

"We really need to determine if antibiotics should be given to patients at the end of life. Do they benefit from treatment?"

The study findings are published in the Feb. 25 issue of Archives of Internal Medicine. The study says that about 70 percent of the 5 million Americans with dementia end up in a nursing home at the end of their lives.

Such patients also suffer from fever and infections at this stage of dementia. Since the medicine is given intravenously, it comes with uncomfortable side effects like diarrhoea.

Excessive use of antibiotics can also lead to the rise of superbugs and the study authors urge the doctors to prescribe the medicines with caution especially in children with earaches and adults with sore throats.

Since the nursing homes can have drug-resistant bacteria, the patients can also spread dangerous infections when they are admitted to hospitals.