A hiccup is an automatic action (a reflex) that the body can't control. During a hiccup your diaphragm (the muscle under your lungs that helps you breathe) contracts. Immediately after this the top of your windpipe (your glottis) closes, making the typical 'hic' sound.
What are hiccups?
Everyone has had hiccups, and knows exactly what they are and what they feel like. Hiccups can be divided into three groups:
- Acute hiccups lasting for minutes or hours. They are usually harmless and last for less than 48 hours.
- Persistent (chronic) hiccups lasting for more than 48 hours, or occurring in recurrent attacks.
- Intractable hiccups lasting for more than one month.
Hiccups affect women and men equally, although persistent hiccups occur much more commonly in men. They happen mainly in the evening.
Persistent or intractable hiccups are more likely to be linked to an underlying illness and you may need medical tests.
What causes hiccups?
Most people have bouts of hiccups from time to time. In most cases they start for no apparent reason, last a short while and then stop. Sometimes they are due to:
- Sudden excitement or emotional stress.
- A temporary swollen stomach caused by overeating or eating too fast, drinking fizzy drinks, or swallowing air.
- A sudden change in temperature (very hot or cold food or drinks, a cold shower, etc).
- Excess smoking.
What causes persistent hiccups?
Persistent hiccups are rare.
- In some cases, persistent hiccups are caused by an underlying disease. Over 100 diseases have been reported to cause hiccups. Some are common, such as acid reflux, and some are rare. You would normally have other symptoms apart from the hiccups.
- In some cases of persistent hiccups there is no apparent cause. However, the persistent hiccups can become exhausting and distressing.
Examples of conditions which can cause persistent hiccups are:
- Certain medicines - examples are steroids, tranquillisers, painkillers containing opiates (such as morphine) and methyldopa (for blood pressure).
- Changes in blood chemistry such as from alcohol, high blood sugar, or lack of calcium or potassium in the blood.
- Gut problems such as acid reflux, stretching (distension) of the stomach, infection of the gallbladder or infection under the diaphragm.
- Other gut conditions that can cause hiccups include hiatus hernia and oesophageal cancer.
- Abdominal masses, such as enlargement of the liver (hepatomegaly) or enlargement of the spleen (splenomegaly).
- A general anaesthetic.
- Conditions affecting the neck, chest or tummy (abdomen). For example, surgery, infections (such as sore throat or pneumonia), swellings or tumours in these parts of the body.
- Some heart conditions - a heart attack or inflammation around the heart.
- Brain conditions such as stroke, head injury or brain infection.
- Hiccups which sometimes occur in the late stages of a terminal illness such as when a person is very ill with advanced cancer.
Do I need any tests?
You are unlikely to need any tests unless you have persistent hiccups lasting more than 48 hours or frequent recurring short bouts of hiccups Unless your doctor can find an obvious cause, they will most likely want to do some tests.
The initial tests are usually blood tests, a heart tracing (electrocardiogram, or ECG) and a chest X-ray. These look for changes such as blood chemistry, chest problems or heart disease.
Other tests may be advised, depending on your individual situation and whether any other medical condition is suspected.
How to get rid of hiccups
Short bouts of hiccups
Most cases need no treatment, as a bout of hiccups usually soon goes.
There are many popular remedies that are said to stop a short bout of hiccups but they are based on people's individual experiences. It is not clear how effective they are, as they have not been tested by research trials. They include the following:
- First, block off all airways by putting fingers in your ears and blocking your nostrils. Then, take a sip or two of water from a glass. It is possible to do this alone (looks a bit silly - but is possible) but you may find it easier with an assistant.
- Drinking water (or cold water).
- Swallowing granulated sugar.
- Biting on a lemon or tasting vinegar.
- Holding your breath, breathing fast, or breathing into a paper bag.
- Gasping after a sudden fright, or sneezing.
- Pulling your knees up to your chest and/or leaning forward to compress the chest.
- Using a technique called the Valsalva manoeuvre. (The Valsalva manoeuvre means trying to push your breath out while you hold your throat and voice box closed.) The way to do this is to take a deep breath in, then keep the air inside you while pushing with your muscles as if to force the air out. This is like pushing in childbirth or straining on the toilet.
If an underlying cause is found then treatment of the underlying cause, if possible, may cure the hiccups. For example, one research study found that many people with persistent hiccups had a gut condition called acid reflux. See the separate leaflet called Acid Reflux and Oesophagitis (Heartburn) for more details. Treating the reflux seemed to help stop hiccups in many cases. Firstly, try any of the popular remedies used to treat short bouts of hiccups (explained above). Also, treat any underlying cause, if possible.
Secondly, medication is sometimes needed to stop persistent hiccups. Various medicines have been used for this. The following medicines may be used for treating adults with hiccups (for children, specialist advice is recommended):
- Chlorpromazine and haloperidol are medicines which can relax the diaphragm muscle or its nerve supply and may stop persistent hiccups.
- For stomach problems such as acid reflux or a stretched (distended) stomach: anti-acid medicines (various types, such as omeprazole) or medicines which help the stomach to empty faster (such as metoclopramide).
- Baclofen - this is a medicine which helps to relax muscles.
- Gabapentin - this can help to relax the nerve supply to the muscle under your lungs that helps you breathe in (the diaphragm).
- Ketamine - an intravenous anaesthetic - is sometimes effective when other treatments have failed.
- Giving a medication called metoclopramide by intravenous injection has been reported to cure hiccups occurring after anaesthetic.
- For people with a terminal illness, sedatives such as midazolam can help to control hiccups and relieve the stress they cause.
Referral to a specialist is often advised for persistent hiccups, either to look for a cause, or to offer more treatment options. Some examples of treatments that have been successfully used for persistent hiccups are:
- Acupuncture or hypnotherapy.
- A device similar to a pacemaker. This is used to stimulate or pace the nerve to the diaphragm (the phrenic nerve) or to stimulate another important nerve in the neck, called the vagus nerve.
For hiccups that continue despite treatment, a phrenic nerve block is occasionally used. This involves interrupting the phrenic nerve - for example, by injecting a local anaesthetic near the nerve. However, this treatment needs to be considered carefully: it carries risks because the phrenic nerve is important in breathing.
Are there any complications of hiccups?
Short bouts of hiccups do not normally cause any problems or complications.
Persistent hiccups may cause complications such as tiredness, exhaustion or poor sleep. Also, they may cause psychological distress or embarrassment. For people who have had recent surgery to the tummy (abdomen), persistent hiccups may delay healing of the scar (wound), because hiccups move the abdominal muscles. This increases the risk of complications with the wound.
Further reading and references
Hiccups; NICE Clinical Knowledge Summary, February 2022 (UK access only)
Moretto EN, Wee B, Wiffen PJ, et al; Interventions for treating persistent and intractable hiccups in adults. Cochrane Database Syst Rev. 2013 Jan 31(1):CD008768. doi: 10.1002/14651858.CD008768.pub2.