Hiccup is a repeated involuntary spasm of the diaphragm followed by sudden rush of air into the lungs causing closure of the glottis which chokes the inflow of further air and produces a characteristic sound. This condition is common and transient and rarely intractable.
Hiccup is said to be the result of irritation of afferent and/or efferent diaphragmatic nerves or medullary center that controls the respiratory muscles – particularly the diaphragm. The exact aetiology is not known, but is supposed to be often caused by gastric distension, alcohol consumption, or swallowing of hot or irritating substances.
Various other causes include metabolic, posterior cranial fossa tumors, and psychological disorders, etc. The exact mechanism is not known though various mechanisms have been described. Hiccup is usually benign, transient, and self-limiting, with a duration of less than one hour without any complication.
Hiccups are classified according to their duration:
1. Acute hiccups are defined as hiccups that last up to 48 hours.
2. Persistent hiccups are hiccups that last for over 48 hours.
3. Intractable hiccups are defined as hiccups that last more than one month or two months.
Intractable hiccups may result in severe discomfort, decreased physical strength, mental depression, and possibly death, if left untreated. Some drugs that are used to treat hiccups can also induce hiccups. Drug-induced causes include benzodiazepines, corticosteroids, antibiotics, opioids, and cytotoxic agents.
Management of hiccups
In most cases, hiccups are benign and self-limiting, not requiring any medical therapy, and relieved by home remedies. Pharmacological and more invasive methods should be reserved for the rare cases of persistent intractable hiccups. For the symptomatic relief and avoidance of potential complications, treatment should be guided by the duration and intensity of the hiccups and initiated by a physician
Baclofen – a centrally acting muscle relaxant – has emerged now as a safe and acceptable first-line drug in most situations. It is effective in doses as small as 5 – 10 mg/day, although occasionally 20 mg three times a day may be needed
Chlorpromazine widely used previously as a first-line drug, almost always works (probably by a diffuse depressant effect on the reticular formation), but does not correct gastric distension. For gastric distension which could be a cause of hiccups, defoaming anti-flatulents, e.g., simethicone and/or prokinetics, e.g., metoclopramide (10 – 20 mg) or itopride may be used.
Haloperidol (tranquiliser) is effective in doses of 2 – 5 mg. Several anticonvulsants have been used to treat intractable hiccups. Phenytoin, valproic acid, and carbamazepine have been effective when used in typical anticonvulsant doses.
Gabapentine has been shown to be effective where CNS lesions are present, or in some other aetiological or non-specific groups.
Anaesthetic agents, e.g., ketamine, has been successful in a dose of 0.4 mg/kg i.e., one-fifth of the usual anaesthetic dose.
Factors known to predispose to hiccups, e.g., excessively spicy, chilly food, alcohol consumption, sudden excitement, emotional stress, etc., should be avoided.
Home remedies alone or in combination are:-
1. Breath holding, the Valsalva manoeuvre, i.e., forced expiration against a closed glottis, breathing into a paper bag, pulling of the tongue, sneezing, swallowing a teaspoonful of granulated sugar, sipping of iced water, milk, or eating ice cream.
2. Kapalbhati pranayama, bharstika, and anulom vilom are useful.
3. Yogasana in which compressing the diaphragm by pulling the knees upto the chest and trying to touch the knee with the nose tip, is helpful.
4. Swallowing large amount of water while closing the nose and ears, and a sudden fright situation are also known to be effective.
Hiccups may cause social embarrassment and distress and interfere with ventilation, medical procedures, and cause wound dehiscence. Hiccups may even lead to oesophagitis, weight loss, cardiac arrhythmias, and insomnia.