A drug that combines a cough suppressant with a heart medication might offer a safer option for calming the agitation that commonly affects people with Alzheimer's disease, an early clinical trial suggests.
The study, of 220 Alzheimer's patients, found that the drug -- called Nuedexta -- generally eased agitation symptoms over 10 weeks.
And it did not worsen patients' problems with memory, thinking and judgment, researchers reported in the Sept. 22/29 issue of the Journal of the American Medical Association.
As Alzheimer's disease progresses, people often go through periods of agitation that can range from restlessness and pacing to aggressive behavior like yelling, fighting and destroying objects.
If those issues can be managed without medication, that's always best, said Dr. Sam Gandy, a professor of neurology and psychiatry at Mount Sinai Hospital, in New York City.
But some people do end up needing medication, which currently means antipsychotic drugs that were developed for conditions such as schizophrenia and bipolar disorder.
"Those drugs basically spilled over into Alzheimer's treatment," said Gandy, who is also a spokesman for the American Federation for Aging Research.
The problem, Gandy explained, is that when given to elderly dementia patients, antipsychotics can have serious side effects, including faster mental decline and heart complications.
The new study tested the effects of Nuedexta, because it's potentially safer and is already on the market for treating a little-known neurological condition called pseudobulbar affect.
The medication is a combination of the cough suppressant dextromethorphan as well as quinidine, a drug that treats abnormal heart rhythms called arrhythmias.
Pseudobulbar affect refers to involuntary outbursts of laughing or crying that can happen to people with brain damage or certain neurological diseases, including Parkinson's, Lou Gehrig's disease and Alzheimer's.
The new findings suggest the drug also helps calm Alzheimer's-related agitation. But it's too soon to know for sure, said Anne Corbett, a dementia researcher who co-wrote an editorial published with the study.
"It's important to remember that these are early results," said Corbett, who is based at King's College London, in the United Kingdom.
"A much larger clinical trial is needed before people can trust in the benefit seen here," she said.
And even though the medication did not seem to speed mental decline, it did have side effects, Corbett pointed out. Almost 9 percent of patients on the drug suffered a fall, and 5 percent developed urinary tract infections, the findings showed.
"Falls in the elderly are always a concern," Gandy agreed. Unfortunately, he added, those falls are also an expected risk with drugs that suppress the central nervous system.
For the study, researchers led by Dr. Jeffrey Cummings, of the Cleveland Clinic Lou Ruvo Center for Brain Health, in Las Vegas, recruited 220 patients with Alzheimer's-related agitation.
First, the researchers randomly assigned 93 patients to take Nuedexta, and 127 to take identical-looking placebo capsules every day for five weeks. At that point, 59 patients who were showing no response to the placebo pills were started on the real drug; another 60 remained on the placebo.
Avanir Pharmaceuticals, which makes Nuedexta, funded the research.
Over 10 weeks, patients on the drug showed a decline in a standard scale used to gauge agitation symptoms. On average, their scores dropped from the 6- to 7-point range to just below 4 points.
"That's a significant change," said Gandy, who was not involved in the study. "The effects would be noticeable and provide meaningful relief."
Since Nuedexta is already on the market, doctors have some understanding of the drug's longer-term safety, Gandy noted. "That means it could be available for widespread use in relatively short order," he said.
However, Gandy added, the U.S. Food and Drug Administration still has to weigh in.
Doctors are technically free to prescribe any approved drug "off-label," for conditions other than the officially approved use. But if Nuedexta were prescribed off-label for agitation, families would have to pay for it themselves, Gandy pointed out.
Why would a drug that combines a cough suppressant and an anti-arrhythmia medication help with agitation? It's not fully clear, Gandy said. According to drugmaker Avanir, Nuedexta is thought to act on brain areas that coordinate "emotional expression."
Both Gandy and Corbett stressed that agitation should first be managed without drugs.
In nursing homes, Gandy said, that often means separating an agitated patient from others, so they can be "reassured" and given time to calm down.
Understanding what's triggering the issue is also key, Corbett said. Sometimes it's pain or even dehydration, she explained; so making sure Alzheimer's patients are comfortable and staying hydrated can help.
Social interaction and "pleasant activities" can also head off agitation, Corbett suggested. "That must, of course, be tailored to the individual," she said, "but could involve looking at old photographs, taking a walk in the garden, or helping with cooking."