What are Antiemetic Drugs?
The term antiemetics is used to refer to drugs that prevent nausea and vomiting or upset stomach. These drugs are also called antiemetic agents, and they work by blocking the signals from the brain that cause nausea and vomiting. A person might use an over the counter or prescription version.
Antiemetic drugs are used for treating nausea and vomiting caused by motion sickness, the stomach flu, acute gastroenteritis, postoperative nausea and vomiting, or morning sickness.
The different classes of antiemetic drugs available include Serotonin 5-HT3 receptor blockers, anticholinergic antiemetics, Neurokinin-1 receptor antagonists, Phenothiazines, and Ondansetron. They are prescribed by a healthcare provider to combat nausea and vomiting.
Dopamine antagonists, such as domperidone (Motilium), chlorpromazine and metoclopramide (Reglan) are the most commonly used antiemetics. These drugs are indicated for motion sickness and postoperative nausea.
Prescribed for Chemotherapy Induced Nausea
Nausea, vomiting and upset stomach are unfortunately a common side effect of chemotherapy treatment. Antiemetic drugs are used before and after chemotherapy to alleviate these symptoms.
Some prescription treatments include:
Serotonin 5-HT3 receptor antagonists:
Granisetron (Kytril, Sancuso), Ondansetron (Zofran, Zuplenz) Dolasetron (Anzemet) and palonosetron (Aloxi)
NK1 Receptor Antagonists:
Rolapitant (Varubi) and Aprepitant (Emend)
Domperidone (Motilium, not available in the US), olanzapine (Zyprexa) and Prochlorperazine (Compazine)
Dronabinol (Marinol) and Cannabis (medical marijuana),
Types of Antiemetic Drugs
Neurokinin-1 Receptor Antagonists
Neurokinin-1 receptor antagonists (NK1 RAs) are a new class of antiemetics that can be used during chemotherapy. In general, NK1 RAs are well tolerated and have few side effects, though insomnia and mood changes are common.
A relatively new class of antiemetics is neurokinin-1 receptor antagonists (NK1 RAs). These medications can suppress chemotherapy-induced nausea and prevent nausea after surgery. In addition, patients should not take NK1 RAs if they are pregnant.
Serotonin 5-HT3 Receptor Blockers
Five-HT3 receptor blockers, or 5-HT3 antagonists, are a new class of antiemetics that inhibit the action of serotonin on the vagal nerve terminals in the gastrointestinal tract.
These receptors send signals directly to the vomiting center in the brain’s medulla oblongata. In the absence of serotonin, 5-HT3 antagonists suppress vomiting by blocking the action of serotonin on vagal afferent nerves.
Phenothiazines are inexpensive and reduce vomiting and nausea. They do this by blocking D2 dopamine receptors and histamine and cholinergic receptors. However, phenothiazines are associated with several side effects.
These side effects include excessive sedation, extrapyramidal symptoms, and metabolic syndrome.
The most commonly prescribed antiemetics are phenothiazines. Phenothiazines block dopamine and 5-HT receptors and have weak inhibitory effects on histamine and muscarinic receptors.
They can be used as single agents or in combination with other antiemetics drugs such as triptans or DHEs. They are also effective in treating psychosis and schizophrenia.
Ondansetron is an antiemetic drug that is used to treat severe nausea and vomiting in dogs and cats. Although ondansetron is commonly prescribed for humans, it is often used in animals for off-label or extra-label purposes. However, it is important to note that ondansetron may have interactions with other medications. You should discuss any changes in dosage or frequency of treatment with your doctor before administering ondansetron to your pet.
Ondansetron acts on the 5-HT3 receptors in the brain. This receptor type is a subtype of serotonin. The serotonin 5-HT3 receptors are found in the vagus nerve terminals, which are in the chemoreceptor trigger zone of the postrema area.
This drug is effective against nausea associated with pregnancy, postoperative treatment, and chemotherapy, but it has no effect on motion sickness. Ondansetron is commonly used to treat nausea and vomiting after undergoing chemotherapy and radiation therapy.
It is also used to treat nausea and vomiting due to surgery and hyperemesis gravidarus during pregnancy. It has a wide range of uses and is listed on the World Health Organization’s Essential Medicines list, alongside other antiemetics such as dexamethasone. In 2006, the brand-name version of ondansetron was the twentieth best-selling drug in the U.S. and continues to be popular today.
Side Effects of Antiemetic Drugs
The adverse effects and common symptoms depend on the type of antiemetic drug you take:
- Bismuth-subsalicylate: dark-colored tongue, grayish-black stools
- Antihistamines: drowsiness, dry mouth
- Cannabinoids: changes in perception, dizziness, blurred vision
- Serotonin 5-HT3 receptor antagonists: constipation, dry mouth, fatigue
- Dopamine antagonists: dry mouth, fatigue, constipation, tinnitus, muscle spasms, restlessness
- Corticosteroids: indigestion, acne, increased appetite and thirst
- Neurokinin receptor agonists: decreased urination, dry mouth, heartburn
Many patients may also experience a variety of other side effects, including constipation, diarrhea, and headache. Some individuals may also experience blurred vision, or photosensitivity.
Regardless of which medication a patient receives, the healthcare provider should carefully consider a patient’s medical history, underlying health issues, and potential side effects before prescribing any medication.
In addition to the above side effects, dopamine receptor antagonists such as metoclopramide may cause irreversible tardive dyskinesia with repeated and prolonged use. Pregnant women should not use these drugs.
How do Antiemetic Drugs Treat Nausea?
The body’s central nervous system and enterochromaffin cells release serotonin, which binds to 5-HT3 receptors. Serotonin 5-HT3 receptor blockers inhibit this binding process and suppress vomiting. Currently, five-HT3 antagonists are approved for use as antiemetics for multiple medical conditions, including nausea and vomiting induced by chemotherapy.
Antiemetic drugs alleviate nausea by working on the central nervous system. Some of the biological processes that cause nausea have an impact on vomiting. The brains are most important in regulating the digestive system.
Antiemesis works in the same location. Some work primarily in the brain and others work more in gastrointestinal nerves controlling the GI function.
In essence central nervous systems and GI systems communicate constantly, and influences will affect both systems if necessary. These two types of communication are unlimited, which explains the numerous ways to relieve nausea.
Is the Antihistamine Antiemetic Medication Cyclizine Addictive?
Cancer patients are prescribed cyclizine as an effective antiemetic to assist with chemotherapy induced nausea and vomiting during treatment. Treating nausea was the intent however according to a study published in the National Library of Medicine:
Cyclizine was taken in large doses intravenously with methadone. The effects initially were of intense stimulation, often with hallucinations, sometimes with aggressive behavior, and occasionally with epileptic fits. Subsequent depressive mood changes occurred often accompanied by a craving for cyclizine. Tolerance to the drug occurred but no clear cut withdrawal syndrome is apparent. It seems that dependence upon cyclizine occurs.
In Utah poison control reported an increase in teens using cyclizine for the hallucination effects.
The antiemetic drug cyclizine is used as an anti-sickness medication. The goal of this antihistamine is to stop nausea and vomiting. It works by blocking a chemical called histamine in your brain that can make you feel sick.
Abuse to Prescription Drugs
Using prescription drugs can still lead to misuse and drug abuse. In recent years, concern over the addictive properties of opioids has led doctors to issue limited-use prescriptions and more closely monitor the use of painkillers.
Nonetheless, if you or a loved one are currently using opioids for medical purposes, it is critical to speak with your doctor if you show any signs of dependence.
Addiction Treatment at Turning Point of Tampa
Turning Point of Tampa uses a 12-step based philosophy, incorporating the principles of the steps, including powerlessness, honesty, and responsibility, into the client’s daily life while in treatment. Therapists often give assignments using 12-step literature, as well as encouraging them to get a sponsor and develop a support network.
Our clinical team collaborates with clients through the 12 steps to identify how spirituality is connected to recovery and help guide them toward developing their own concept of a higher power. Many of our therapists and staff have personal experience with the 12-step method of recovery. Coupled with our other therapeutic modalities, the 12-step approach is another tool we use to give client a well-rounded introduction to recovery.
At Turning Point of Tampa we offer a comprehensive continuum of care, including primary and extended care programs, intensive outpatient, and weekly aftercare groups. Our program treats various addictions in the comfort of our serene, tranquil campus.
At Turning Point of Tampa we offer individual and group therapy, support groups, and many other addiction treatment options to address addiction and substance abuse.
Cannabinoid Hyperemesis Syndrome
Cannabinoid hyperemesis syndrome (CHS) is a condition where individuals who consume large amounts of cannabis (marijuana) repeatedly experience nausea and vomiting.
This condition can be caused by various health issues, including the over-stimulation of the endocannabinoid system, which is a system of receptors in the body that responds to the compounds found in marijuana. Risk factors for cannabinoid hyperemesis syndrome include chronic cannabis use over a prolonged period of time.
Long Term Effects of Weed
Generally, the long-term effects of weed use are more severe than those associated with its short-term effects. However, there is one exception: cannabidiol, which is found in cannabis plants, may offer protection against THC’s negative impacts.
Regardless of its effects, long-term weed use may change a person’s personality. Specifically, heavy pot smokers may experience general and social anxiety.
Codeine and Weed
Codeine and weed are two drugs that are often used together. Codeine is an opioid painkiller that is prescribed for moderate to severe pain relief. Weed is a psychoactive drug that alters how the mind perceives things.
Codeine can be addictive and lead to tolerance, which means you need more of it to get the same effect as when you first started taking it. Codeine also has a high potential for abuse because it can be injected or taken intravenously as well as orally through tablets or liquids.
Side Effects of Marijuanas Tea
Marijuana tea is a cannabis-infused drink that can be made by steeping the marijuana leaves in hot water for a certain amount of time. It is not as potent as smoking marijuana, which means that the side effects of marijuanas tea are less intense. Some of the common side effects of marijuana teas include dry mouth, dizziness and increased appetite.