one, which modulates glutamate).
Optimizing Acetylcholine
One way to ensure optimal acetylcholine function is to
avoid a broad class of very common “anticholinergic”
drugs. Many of these drugs are widely used and available
over the counter, used to treat everything from allergies to
insomnia.
These drugs, as the word suggests, block the
neurotransmitter acetylcholine, and continuous use can
cause cognitive problems in as little as sixty days.^11 But
even occasional use of a strong anticholinergic can cause
acute toxicity. The symptoms are often remembered by med
school students with the mnemonic “Blind as a bat (dilated
pupils), red as a beet (flushing), hot as a hare (fever), dry as
a bone (dry skin), mad as a hatter (confusion and short-term
memory loss), bloated as a toad (urinary retention), and the
heart runs alone (rapid heartbeat).”
Neurotransmitters are more than just the messages they
contain—sometimes they are essential for keeping neurons
healthy. Alarming research published in JAMA Neurology
has shown that regular users of anticholinergic drugs had
lower brain glucose metabolism and poorer cognitive
abilities (including weaker short-term memory and
executive function). Subjects even showed altered brain
structures in MRI scans, displaying lower brain volume and
larger ventricles (the cavities inside the brain). The
anticholinergic drugs taken by these subjects included
nighttime cold medicines, over-the-counter sleep aids, and
muscle relaxants—all of which block acetylcholine.