Pitolisant Boosts Memory Accuracy by 11 Percent in Small Trial but Does Not Enhance Healthy Cognition

A drug that raises histamine levels in the brain improved memory accuracy by 11 percent in a trial of 60 volunteers, according to research published in Nature Communications. Michael Colwell at the University of Oxford led the study. Volunteers received either pitolisant, an existing narcolepsy treatment that binds to histamine 3 receptors, or a placebo.

Researchers then scanned their brains with MRI while they completed memory tests. Scans showed increased connectivity between histamine-producing regions and the hippocampus in those given pitolisant. These participants retrieved information learned during the session with 11 percent greater accuracy than the placebo group.

Histamine receptors are densely packed in brain areas tied to learning and memory, Colwell noted. Older antihistamines that crossed into the brain had previously been linked to reduced recall. Roland Seifert at Hannover Medical School said the results confirm that animal findings on histamine and memory apply to humans.

Holger Stark at Heinrich Heine University said pitolisant has restored impaired cognitive function in disease settings but does not enhance cognition beyond normal levels. People taking pitolisant for narcolepsy or Prader-Willi syndrome have reported better attention and alertness, Stark added. Colwell cautioned against using the drug to boost healthy memory, citing likely effects on sleep.