When food enters the stomach, it is churned with stomach acid and digestive enzymes. This both chemically and mechanically digests food partially so that it can be further digested in the small intestine where the majority of nutrients are absorbed. The fluid containing partially digested food, gastric acid, digestive enzymes and water that exits the stomach is known as gastric chyme. It is released in a controlled manner into the small intestine and this release from the stomach is known as gastric emptying.
What is a slow stomach?
The term slow stomach is a common way of describing a medical condition known as delayed gastric emptying. However, it can be misleading since some people refer to the entire abdomen or digestive tract as the stomach. Therefore in these instances a slow stomach can also refer to other conditions such as constipation. For the purpose of this article, the focus will be on delayed gastric emptying.
The stomach releases gastric chyme in a controlled manner through the pyloric sphincter which is the end portion of the stomach. This ensures that the small intestine is not suddenly flooded with undigested food but at the same time has to ensure that the stomch does not become excessively stretched with too much of food. In some people, however, the outflow from the stomach is very slow.
Read more on weak bowel movements.
Emptying from the Stomach
The end portion of the stomach which connects to the small intestine is known as the pylorus. A band of smooth muscle controls flow out of the stomach and this is known as the pyloric sphincter. Therefore it is also known as the pyloric pump. Not only does it open and close to release the stomach contents but it also prevents fluids like bile in the duodenum (small intestine) from entering the stomach.
The control of the opening and closing of the pyloric sphincter is controlled by the acidity within the stomach, nerve impulses from the stomach wall and duodenal wall as well as certain hormones. It is a complex interplay to ensure that digestion is coordinated for the maximum utilization of food. The entire process of stomach digestion and emptying after eating a meal can last for several hours.
Signs and Symptoms
The signs and symptoms of delayed gastric emptying can be similar to may other more common digestive conditions. The main symptoms include:
- Nausea especially after eating.
- Projectile vomiting.
- Fullness after a few bites of food.
- Stomach pain (upper left abdominal pain).
- Excessive burping (belching).
- Abdominal cramps.
- Lack of appetite.
- Foul-smelling belches (like sulfur or rotten eggs).
Delayed gastric emptying can also result in low blood glucose levels and unintentional weight loss which may occur with a reduced appetite. It is important to note that delay gastric emptying may occur with or be caused by conditions like gastritis and peptic ulcers which also present with the same symptoms. Therefore delayed gastric emptying can be missed for long periods while these more common conditions are being treated.
Read more on projectile vomiting.
Causes of Slow Stomach
There are two main reasons why delayed gastric emptying may occurs. First is a problem with the nerves, muscles or hormones that impeded outflow from the stomach which is collectively referred to as gastroparesis. Second is a mechanical obstruction preventing outflow from the stomach which is known as gastric outlet obstruction.
- Diabetes neuropathy (nerve damage) occurs with long term poorly controlled diabetes mellitus and this may affect the nerves controlling gastric emptying.
- Surgery to the vagus nerve and/or stomach may damage the vagus nerve that controls the pyloric sphincter.
- Gastroesophageal reflux disease (GERD) can also affect gastric emptying.
- Eating disorders like anorexia nervosa and bulimia may also damage the nerves and muscles responsible for gastric emptying.
- Hypothyroidism where there is a slow down of the metabolism due to low thyroid hormone levels can also slow down gastric emptying.
- Drugs, both pharmaceutical and illicit drugs, may impair gastric empting as is seen with opiates, anticholinergics, calcium channel antagonists among others. Chemotherapy may also be reponsible.
- Viral infections particularly those infections involving the stomach and nerves can hamper control of gastric emptying.
- Parkinson’s disease where there is slowness of movement and nerve dysfunction can affect the stomach nerves and muscles in later stages.
- Amyloidosis of the stomach muscles and scleroderma may cause hardening and thereby dysfunction of the muscles controlling the pyloric pump.
Gastric Outlet Obstruction
- Swelling of the pylorus due to inflammatory conditions like gastritis and peptic ulcers.
- Hardening or narrowing of the pyloric sphincter (pyloric stenosis) which may occur with scarring of an ulcer in the duodenum and adult hypertrophic pyloric stenosis.
- Polyps in the stomach which are benign growths from the stomach wall.
- Gallstones that are large can block the outflow from the stomach.
- Pancreatic pseudocysts which can arise a period of time after pancreatitis.
- Cancer of the stomach, duodenum, pancrease or gallbladder.
- Congenital duodenal webs which are present from birth.
Diagnosis of Stomach Slowness
Delayed gastric emptying cannot be diagnosed by the symptoms alone. Diagnostic investigations are necessary to confirm the diagnosis. These investigations include:
- Upper GI endoscopy
- Barium x-ray
- Gastric scintigraphy
- Gastric manometry
Always consult with a doctor about the possibility of delayed gastric empting to ensure that the necessary investigations are conducted to confirm such a diagnosis.
The treatment of a slow stomach depends on the underlying cause. Sometimes surgery may be necessary to remove the causative factor and improve gastric emptying. Dietary modificationi s helpful in managing the condition and this involves eating many small meals in a day and avoiding certain foods. However, this is not a treatment for the underlying problem which needs to be attended to so that the condition does not worsen.
Certain drugs can speed up gastric emptying. This includes:
- Metoclopramide is a prokinetic agent that stimulates stomach muscle contractions.
- Erythromycin is an antibiotic that also simulates the muscles of the stomach.
However, the condition will not resolve if the underlying cause is not properly treated and managed. Other drugs may be prescribed to control the symptoms such as antiemetics for nausea and antacids for heartburn.