Hiccups occur when there is a sudden, involuntary movement of the diaphragm. This muscle is located in the lower part of the chest, between the thorax and the abdomen, and contracts rhythmically and continuously to help us breathe.
It descends when we inhale, so that the lungs can fill with air, and relaxes when we exhale, so that the lungs can expel the air through the nose and mouth. When the diaphragm is disrupted, it descends abruptly, causing air to rush into the throat and strike the larynx.
This causes the vocal cords to close rapidly, producing the characteristic ‘hic’ sound. It is a reflex action, but unlike sneezing or coughing, hiccups serve no known protective function.
Hiccups are especially common in childhood, even from the first three months of gestation and in newborns. According to some hypotheses, the movements of hiccups in the fetus prepare the respiratory muscles to perform their function immediately after birth.
Types of hiccups
- Benign or isolated hiccups: This is the most common form, consisting of brief, isolated, and involuntary contractions of the diaphragm that often go unnoticed. An episode of benign hiccups lasts from a few seconds to a few minutes. It is considered normal and does not require treatment. It is usually due to lifestyle and dietary habits.
- Acute (persistent) hiccups: Repetitive contractions, lasting at least 48 hours, which can be noisy and relatively bothersome for the patient and those around them. They tend to disappear spontaneously and may be due to dietary causes or the adverse effect of a medication.
- Chronic, intractable, or refractory hiccups: Muscle contractions last for several days and do not resolve spontaneously. They can be debilitating and often require treatment. They may be a symptom of an underlying medical condition.
Possible causes of hiccups
Hiccups can start without an apparent cause, but usually there is some factor that irritates and alters the normal functioning of the diaphragm:
- Eating too much and/or too quickly
- Eating very hot or spicy foods
- Drinking alcohol, soft drinks, or other carbonated beverages
- Smoke
- Emotional situations, such as excitement, anxiety, or nervousness
- Sudden changes in body temperature
- Certain medications
- There is a possibility of developing a condition that irritates the phrenic nerve, which controls the diaphragm. These conditions can include pleurisy (irritation or inflammation of the pleura, the lining around the lungs) or pneumonia.
- Metabolic disorders, swelling or irritation of the stomach or throat, disorders of the central nervous system, tumors or cerebrovascular diseases, which in the long run affect the body in this way.
There are three levels of action you can take to try to make hiccups disappear.
- Breathing: Some sources mention a drop in blood carbon dioxide levels as a possible cause of hiccups, which can be remedied with various breathing exercises. Holding your breath (apnea) for about ten to fifteen seconds or slowing your breathing rate (breathing slowly and repeatedly into a paper bag) can be effective. There is also a breathing exercise that helps to compress the diaphragm: taking a deep breath to reach the space below the ribs.
- Diaphragm: Acting directly on it can calm hiccups. You can lie on the floor and bring your knees to your chest, holding this position for a couple of minutes. You can also bend forward and try to touch your toes with your hands, which will compress the chest and relieve the spasm.
- Distraction: Trying to stop hiccups only makes them worse, since anxiety is one of their main triggers. If you forget about the hiccups, they’ll probably disappear on their own. The famous “startle” method is based on this premise: if something catches our attention, the body goes on alert and the diaphragm relaxes. There are several alternative methods, such as eating a slice of lemon, sucking on ice, or taking a spoonful of sugar and holding it in your mouth until it dissolves.