Parasympatholytic

Part of speech: adjective, noun

Definitions

  1. A substance that blocks the action of the parasympathetic nervous system ; a drug that inhibits parasympathetic nerve impulses to cause effects such as increased heart rate or reduced secretions ; any agent that counteracts parasympathetic functions by preventing neurotransmitter activity
  2. An agent that suppresses the parasympathetic nervous responses ; a chemical that interrupts the transmission of signals in parasympathetic nerves to lessen bodily rest-and-digest activities ; a compound that diminishes parasympathetic influence by antagonizing receptors
  3. A compound that opposes parasympathetic nervous effects ; a medication that reduces parasympathetic nerve stimulation to elicit physiological changes like dilated pupils or relaxed muscles ; a pharmacological agent that interferes with parasympathetic neurotransmission to alter bodily functions

Etymology: This is a technical coinage, built deliberately from Greek parts rather than evolving through speech. Its core is "sympatho-", from the Greek "sympathēs" meaning "affected together" or "sharing feeling", a term that came to describe the nervous system's "fight or flight" branch, which speeds the heart and readies the body for action. The prefix "para-" comes from the Greek "para", meaning "beside" or "alongside", and in anatomy it names the parasympathetic branch that runs alongside and often works against the sympathetic one, slowing the heart and stimulating digestion. The ending "-lytic" comes from Greek "lytikos", "able to loosen or dissolve", which is also the root of "-lysis" in words like "analysis". Put together, the parts describe a substance that loosens or dissolves the action of the parasympathetic system, which is exactly what the drug class does when it blocks the nerve signals involved. Atropine is the classic example of such an agent, though the word itself belongs to the modern vocabulary of pharmacology rather than to any ancient Greek usage.

Synonyms: anticholinergic

Antonyms: parasympathomimetic