Medicines from class of drugs commonly used by the elderly, including Benadryl and Dramamine, can cause impaired thinking, study finds
The family of drugs that includes the over-the-counter medications Benadryl, Dramamine, Excedrin PM, Sominex and Tylenol PM can double the risk of impaired thinking in elderly African Americans, and presumably in Caucasians as well, researchers said Tuesday.
The family, called anticholinergics, blocks the activity of the neurotransmitter acetylchoine, and also includes the prescription drugs Paxil, Detrol, Demerol and Elavil. Most of the anticholinergics are used by the elderly to aid sleep and to relieve bladder leakage problems. The drugs have previously been shown to increase the risk of delirium as well. Delirium is a form of sudden-onset cognitive impairment.
Blacks are already known to be at high risk for cognitive impairment, one reason that researchers focused specifically on them. The team, led by Dr. Malaz Boustani of the Regenstrief Institute at the Indiana University School of Medicine, took advantage of an ongoing study called the Indianapolis Ibadan Dementia Project, whose aim is to compare risk factors for dementia in blacks in Indianapolis and Yoruba in Ibadan, Nigeria. The new study involved 1,652 Indianapolis blacks who did not suffer cognitive impairment when they entered the study. Researchers collected information from participants about their use of the drugs, and also collected medicine bottles from their homes during each assessment. They found that 11% of the subjects used anticholinergics.
After six years of follow-up, the team reported in the journal Neurology, patients taking one anticholinergic were 46% more likely to suffer from cognitive impairment, while those taking two were twice as likely. The risk was somewhat higher in the patients who did not carry what is known as the E4 variant of the gene APOE, which plays a role in the metabolism of triglycerides, a form of cholesterol. That finding was somewhat surprising because APOE E4 increases the risk of Alzheimer’s disease.
“Simply put, we have confirmed that anticholinergics, something as seemingly benign as a medication for inability to get a good night’s sleep or for motion sickness, can cause or worsen cognitive impairment, specifically long-term mild cognitive impairment which involves gradual memory loss,” Boustani said in a statement. “I tell all my [elderly] patients not to take these drugs….Our research efforts will now focus on whether anticholinergic-induced cognitive impairment may be reversible.”
A list of medications with anticholinergic effects can be found here.
