Nausea and Vomiting - Common Causes and Management

When the stomach muscles involuntarily contract and forcefully expel its contents up along the oesophagus (food pipe) and out through the mouth, it is called vomiting or emesis. Vomiting can be triggered by various reasons, one of which is the body gets rid of harmful substances from the stomach. There are a number of other triggers such as stress, motion sickness etc. Vomitus is the material that is expelled out and it indicates what the person had recently eaten.

Nausea is the unpleasant feeling of a need to vomit. Nausea and vomiting can occur separately or together.

Vomiting empties the stomach and often relieves nausea, at least for a while. Nausea is a symptom and vomiting is a sign. They are usually harmless and everyone experiences mild nausea and vomiting at some time. However, if the complication is chronic, it's ideal to seek professional clinical guidance for timely care.

Anatomy and Physiology of Nausea and Vomiting

Nausea and vomiting occur as a result of the vomiting centre in the brain being activated. They can accompany many metabolic, toxic, and structural disorders.

The Digestive System

With solids, the pressure at certain points in the digestive tract increases and the stomach breaks down the food into minute particles and pushes it into the intestine. This muscle activity in the GI (Gastro-Intestinal) tract is disrupted due to nausea. Stomach acid and intestinal contents flow back into the stomach, causing irritation and vomiting.

The Role of the Brain

The vomiting centre located in the medulla of the brain receives signals from the cortex, hypothalamus, vestibular centres, and the gut. Nausea is related to increased activity in the vomiting centre. The CTZ (Chemoreceptor Trigger Zone) detects various toxins in the blood and other fluids and relays this information to the vomiting centre.

The Autonomic Nervous System

The vomiting centre in the brain processes the signals it receives and regulates the response of the body to unpleasant stimuli and sensations. It performs this function by activating the autonomic and somatic motor responses. While the vomiting center can activate the autonomic responses, the autonomic system itself does much more than just regulate nausea and vomiting.

Common Causes of Nausea and Vomiting

Vomiting occurs due to different reasons, mainly depending on age and timing. In children, vomiting is mostly a result of food poisoning due to viral or bacterial infections, certain food allergies, overeating, or even coughing.

The most common causes of nausea and vomiting are disorders involving the digestive tract or the brain, or any ingested substances. 

An abrupt onset of either nausea or vomiting can occur due to an infection, or a disorder of the central nervous system. When the condition is acute, the cause is usually inflammation or a structural lesion. Chronic, intermittent vomiting can result from an inflammatory or obstructive condition in the GI tract, or due to other deeply ingrained triggers such as motion sickness, stress, depression etc. 

Without other symptoms, chronic vomiting may be self-induced, and chronic nausea without vomiting could indicate psychogenic problems.

Gastrointestinal Causes

When vomiting is due to GI causes, it is generally an acute condition.

• Gastritis: When the lining of the stomach becomes inflamed, it produces less mucous and acid. This condition is called gastritis and can cause nausea and vomiting.
• Peptic Ulcers: Peptic ulcers are open sores in the lining of the stomach (gastric ulcers) or the intestine (duodenal ulcers), mostly due to infection by bacteria called Helicobacter pylori. Abdominal pain, nausea, and vomiting are common complaints.
• Gastroenteritis: Gastroenteritis is an acute infection of the intestines that causes diarrhoea, abdominal pain, nausea or vomiting, and fever, commonly caused by norovirus in adults and by rotavirus in children.
• Food Poisoning: Food poisoning is an infection of the digestive tract caused by viruses, bacteria, or parasites. Children, pregnant women, and people with weak immunity are at greater risk of food poisoning and developing complications.
• Irritable Bowel Syndrome: IBS (Irritable Bowel Syndrome) is a common, chronic GI disorder. The gut becomes more sensitive and causes changes in the way muscles in the bowel contract. Diarrhoea and/or constipation are the two most common symptoms. Many people also experience nausea which is usually triggered by certain foods or stress.

Non-Gastrointestinal Causes

When there is a pattern of ongoing or recurring vomiting, it is termed chronic vomiting. Most of the non-GI causes of vomiting are categorised as chronic conditions.

• Motion Sickness: Motion sickness or sea sickness is a common condition of feeling unwell in a moving vehicle. Nausea is accompanied by vomiting, dizziness, or cold sweat.

The vestibular apparatus (organs of balance in the inner ear) are connected to the vomiting centre in the brain. When the body seems unbalanced in a moving vehicle, the senses are confused. This is the reason for nausea from the movement of a boat or travel in a car or plane. 

• Migraines: A migraine is a typical pulsating or throbbing pain on one or both sides of the head, and nausea and vomiting are common symptoms. Not only are they sometimes more disabling than the actual pain, nausea and vomiting can delay the use of oral medicines. 
• Vertigo: Vertigo is a kind of dizziness that arises when someone feels that they are spinning or the environment around them is spinning. It is related to the way the inner ear handles balance. Inner ear infections or inflammation of the vestibular nerve can cause vertigo with nausea and vomiting along with other symptoms.
• Pregnancy: Nausea and vomiting are quite common during pregnancy, beginning around the ninth week and reducing around the fourteenth week. Commonly referred to as “morning sickness”, nausea and vomiting can occur at any time during the day. Usually, there is no harm to the foetus. However, hyperemesis gravidarum (severe nausea and vomiting), can affect the foetus’s weight at birth and requires medical treatment. 
• Medication Side-Effects: Nausea is a common side effect of many medications. These include antibiotics like erythrocin, aspirin, NSAIDs (Non-Steroidal Anti Inflammatory Drugs) like ibuprofen. Many individuals may experience nausea due to other medications as well. It is ideal to consult with your physician to ascertain potential side-effects of any new medication.

Treatment of Nausea and Vomiting

It is important to know about the symptoms and take a detailed medical history. A physical exam will follow and tests may be required. Conditions like pregnancy, diabetes, kidney disease, or cancer are important considerations while planning treatment. 

Non-Pharmacological Interventions

There are many nonpharmacologic techniques or complementary medicine practices:

• When chemotherapy is the cause, acupuncture has provided relief in some people.
• deep breathing techniques, hypnosis, meditation

Pharmacological Interventions

For adults, antiemetics (drugs to relieve vomiting) are prescribed:

• Antihistamines 
• Prochlorperazine or metoclopramide 
• Ondansetron or dolasetron 

Intravenous Fluids and Nutrition

Intravenous fluids and/or drugs like corticosteroids and antiemetics are required:

when there are significant dehydration or electrolyte imbalances

• if a person is vomiting actively 
• if oral liquids are not tolerated

Surgery

For children who experience persistent vomiting and reflux, a surgical procedure called fundoplication can be performed. It is used as a last resort when a child has not responded to medical treatment or has developed complications.
Surgical procedures for nausea and vomiting include gastrotomy, pyloroplasty, or gastrectomy.

Managing Nausea and Vomiting at Home

Many acute conditions can be managed at home with:

Rest and Hydration

It is important to rest and avoid activity after a meal. Small sips of clear fluids and water are recommended. ORS (Oral Rehydration Solution) is useful to replace electrolytes.

Dietary Modifications

• solid foods are better avoided
• smaller, more frequent meals will also help. 
• easily digested foods like bread, toast, and crackers to be tried initially, and If these can be kept down, cereal, rice, and salty or high-protein food can be consumed. 
• fatty foods and spicy items should be avoided.

Over-The-Counter Medications

Common medications like Dramamine can help to counter motion sickness.

Home Remedies

Some of the popular home remedies include:

• pregnant women eating crackers before getting out of bed in the morning and a high protein snack like cheese before bedtime.
• sweet drinks like fruit juices, and salty snacks 
• ginger biscuits and ginger tea.
• Cardamom, peppermint, and spearmint, with inhalation of essential oils like lavender.

It is important to note that these strategies are merely observational and don’t hold proven clinical significance. Moreover, the effects may be subjective for different individuals.

Conclusion

Apart from causing only discomfort in most instances, vomiting could lead to complications like:

• aspiration (inhaled vomitus entering the lungs)
• dehydration and electrolyte imbalances
• undernutrition and weight-loss
• a tear in the lining of the oesophagus 
• It is important to get medical help if:
• vomiting lasts more than forty-eight hours
• the vomitus is green or greenish-yellow
• there are frequent episodes of regular vomiting
• there is sudden, severe abdominal or chest pain

Frequently Asked Questions
1. What Is The Difference Between Nausea And Vomiting?

Nausea is an uneasy or sickly feeling that indicates an urge to vomit, but it does not always result in vomiting. Vomiting is the throwing up of food and other contents in the stomach.

2. What Should I Do If I Feel Nauseous But Cannot Vomit?

Taking small sips of water or herbal tea will help. Cold or frozen drinks, non-acidic fruit juices, or clear soup can also relieve the discomfort.

3. Can Anxiety Cause Nausea And Vomiting?

The stress and anxiety which accompanies cancer treatment can cause nausea and vomiting. Women are more likely to experience anxiety-related nausea and vomiting during cancer treatment if they:

• had morning sickness while they were pregnant, 
• often complain of motion sickness

4. How Long Does It Take For Nausea And Vomiting To Resolve?

Nausea usually lasts a few days. It requires medical consultation if pregnancy is suspected and if it lasts more than a week.
Vomiting usually subsides within a day after an episode and can be managed at home, unless it’s because of injury or there is dehydration.