In many cases, only a single hemidiaphragm, usually the left one, is affected, although both may be involved. Treatment
Hiccups are normally waited out, as any fit of them will usually pass quickly. Folk cures for hiccups are common and varied, but no effective standard for stopping hiccups has been documented. Hiccups are treated medically only in severe and persistent (termed "intractable") cases.Numerous medical remedies exist but no particular treatment is known to be especially effective, generally because of a lack of high-quality evidence. Many drugs have been used, such as baclofen, chlorpromazine, metoclopramide, gabapentin, and various proton-pump inhibitors. Hiccups that are secondary to some other cause, like gastroesophageal reflux disease or esophageal webs, are dealt with by treating the underlying disorder. The phrenic nerve can be blocked temporarily with injection of 0.5% procaine, or permanently with bilateral phrenicotomy or other forms of surgical destruction. Even this rather drastic treatment does not cure some cases, however.Haloperidol, metoclopramide, and chlorpromazine are used in cases of intractable hiccups. Effective treatment with sedatives often requires a dose that renders the person either unconscious or highly lethargic. Hence, medicating with sedatives is only appropriate short-term, as the affected individual cannot continue with normal life activities while under their effect.A vagus nerve stimulator has been used with an intractable case of hiccups. "It sends rhythmic bursts of electricity to the brain by way of the vagus nerve, which passes through the neck.
They may also present as brief but distracting or painful interruptions in normal breathing, with sudden momentary pain of the throat, chest, or abdomen. Causes
Pathophysiological causes
Swallowing air excessively
Gastroesophageal reflux
Hiatal hernia
Rapid eating
Carbonated beverages, alcohol, dry breads, and some spicy foods
Opiate drug use
Laughing vigorously or for a long timeHiccups may be triggered by a number of common human conditions. In rare cases, they can be a sign of serious medical problems. In rare cases, hiccups can be the sole symptom of myocardial infarction. Pre-phrenic nucleus irritation of medulla
Kidney failure

CNS disorders
Stroke
Multiple sclerosis
Meningitis

Nerve damage
Damage to the vagus nerve after surgery

Other known associations
Although no clear pathophysiological mechanism has been described, hiccups is known to have been the initial symptom of Plasmodium vivax malaria in at least one documented case. Evolutionary theories
The burping reflex hypothesis
A leading hypothesis is that hiccups evolved to facilitate greater milk consumption in young mammals. The coordination of breathing and swallowing during suckling is a complicated process. Some air inevitably enters the stomach, occupying space that could otherwise be optimally used for calorie rich milk.The hypothesis suggests that the presence of an air bubble in the stomach stimulates the sensory (afferent) limb of the reflex through receptors in the stomach, esophagus and along the underside of the diaphragm. This triggers the active part of the hiccup (efferent limb), sharply contracting the muscles of breathing and relaxing the muscles of the esophagus, then closing the vocal cords to prevent air from entering the lungs. This creates suction in the chest, pulling air from the stomach up into the esophagus.