How Do Antiemetic Agents Work?

Antiemetic agents are a class of medications used to treatnauseaand vomiting. These two symptoms are very common and are caused by different medical conditions, therapies, procedures, and medications. Although vomiting is considered to be a protectivereflexaction of the body to expel toxic substancesinthestomachand gut, antiemetic medications are often necessary to suppress vomiting, especially to preventdehydration.

Antiemetic agents are administered viaoralandintravenousroutes.

Types of antiemetic agents:

• Antihistamines: help prevent nausea and vomiting caused bymotion sickness
• Antiemetic forstomach flu: relieves the symptoms ofgastroenteritis
• Antiemetic duringpregnancy: relievesmorning sickness
• Antiemetic aftersurgery: prevents after-effects ofanesthesia
• Antiemetic forcancerandchemotherapy: prevents side effects of chemotherapy and improves thequality of life

Antiemetic agents should be appropriately prescribed by a healthcare professional, considering the person in need of it, the underlying cause, the severity of the case, and the possible side effects.

Antiemetic agents work in the following ways:

• Vomiting is controlled by the vomiting center in thebrain, which is activated by triggers such as strongsmell, thoughts and motion.
• Antiemetic agents bind to the receptors in the vomiting center of thebrain stemand block their signaling pathways (that lead to nausea and vomiting), thus reducing the nauseasensation.
• Theemeticresponse is mediated through multiple neurotransmitters (chemical messengers) includinghistamine,dopamine,serotonin,acetylcholine, and neurokinin.
• Neurotransmitters are the cells that receive the signals to send anerveimpulse.
• Antiemetic agents block the action of these neurotransmitters, which prevents the signals of nausea to reach the brain that helps tocontrolnausea and vomiting.
• They inhibit the stimulation of thegastrointestinal tract,diaphragm, andabdominal muscles.
• In addition, they produce a calming effect on the brain that leads to slight drowsiness.

Apart from vomiting, antiemetic agents are also used in conditions such as:

• Chemotherapy-induced nausea and vomiting
• Motion sickness
• Postoperativenausea and vomiting
• Nausea and vomiting of pregnancy
• Side effects ofopioidanalgesics
• 胃肠炎(infectionandinflammationof thedigestive system)
• Food poisoning
• Parkinsonism(conditionthat causes a combination of the movement abnormalities seen in Parkinson'sdisease)
• Cough
• Insomnia(trouble falling and/or staying asleep)
• Vertigo(a sensation of feeling offbalance)
• Allergic reactions such asrash,itching, and流鼻涕
• Meniere's disease (disorder of theinner earthat can lead to dizzy spells and hearing loss)
• Anorexia(an eating disorder characterized by markedly reduced appetite or total aversion tofood)

Common side effects include:

• Headache
• Constipation
• Fatigue
• Drowsiness
• Dizziness(feeling faint, weak, or unsteady)
• Dry mouth
• Loss of appetite

Other rare side effects include:

• Blurred vision
• Slow heartbeat
• Confusion
• Unusual weakness
• Hallucinations (involve hearing, seeing, feeling, smelling, or even tasting things that are not real)
• Hypertension/hypotension
• Urinaryretention

Information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with yourdoctoror药剂师to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking yourmedicationand never change your dose or frequency without consulting your doctor.

Drug names include:

• Akynzeo
• Alka-Seltzer PlusAllergy
• Amisulpride
• Antivert
• Aprepitant
• Barhemsys
• Benadryl
• Benadryl Allergy Dye-Free LiquiGels
• Bonine
• Bonjesta
• Cesamet
• Children's Benadryl Allergy
• Children's Emetrol
• Children's Triaminic Thin Strips Allergy
• Cinvanti
• Compazine
• Compazine Spansules
• Diclegis
• Dimenhydrinate
• Diphenhydramine
• Doxylamine/pyridoxine
• Dramamine
• Dramamine Less Drowsy Formula
• Dronabinol
• Droperidol
• Emend
• Emetrol
• Fosaprepitant
• Fosnetupitant
• Hydroxyzine
• Inapsine
• Maldemar
• Marinol
• Meclizine
• Meclozine
• Meni D
• Metoclopramide
• MetozolvODT
• Nabilone
• Nauzene
• Netupitant/palonosetron
• Nytol
• PediaCare Children's Allergy
• Phenadoz
• Phenergan
• Phosphoratedcarbohydrate
• Phosphoric acid/dextrose/fructose
• Prochlorperazine
• Prochlorperazine edisylate
• Prochlorperazine mesylate
• Promethazine
• QlearQuil Nighttime Allergy Relief
• Reglan
• Rolapitant
• Scopace
• Scopolamine
• SimplySleep
• Sodium citrate/dextrose/fructose
• Sominex
• Syndros
• Tigan
• Tranquil Nighttime Sleep Aid
• Transderm Scop
• Trimethobenzamide
• Unisom SleepGels
• Unisom SleepMelts
• Varubi
• VertiCalm
• Vistaril
• ZzzQuil