It can also be caused by certain medical conditions, such as:

- Ulcers

- Abscesses

- Upper respiratory tract infections

- Inflammation or infection of the mouth, tongue, or throat (esophagitis, pharyngitis, tonsillitis, epiglottitis)

- Immune disorders

- Oral or throat cancer

Odynophagia may have environmental or behavioral causes, such as:

- Very hot or cold food and drinks

- Taking certain medications

- Using drugs, tobacco, or alcohol

- Trauma or injury to the mouth, throat, or tongue

Food bolus obstruction is most commonly caused by Schatzki rings, which are mucosal rings of unknown cause in the lower esophagus. Foodstuff jams into the esophagus due to the narrowing caused by the ring. An increasingly commonly recognized cause for esophageal food bolus obstruction is eosinophilic esophagitis, which is an inflammatory disorder of the mucosa of the esophagus, of unknown cause. Many alterations caused by eosinophilic esophagitis can predispose to food boluses; these include the presence of multiple rings and narrowing of the lumen. When considering esophageal dilation to treat a patient with food bolus obstruction, care must be made to look for features of eosinophilic esophagitis, as these patients are at a higher risk of dilation-associated complications.

Other conditions that predispose to food bolus obstructions are esophageal webs and peptic strictures. Food boluses are common in the course of illness in patients with esophageal cancer but are more difficult to treat as endoscopy to push the bolus is less safe. Patients with esophageal self-expandable metallic stents may present with food boluses lodged within the stent lumen. Rarely disorders of movement of the esophagus, such as nutcracker esophagus, can predispose to food bolus obstruction.

An esophageal food bolus obstruction (or steakhouse syndrome) is a medical emergency caused by the obstruction of the esophagus by an ingested foreign body. It is usually associated with diseases that narrow the lumen of the esophagus, such as eosinophilic esophagitis, Schatzki rings, peptic strictures, webs, or cancers of the esophagus; rarely it can be seen in disorders of the movement of the esophagus, such as nutcracker esophagus. While some esophageal food boli can pass by themselves or with the assistance of medications, some require the use of endoscopy to push the obstructing food into the stomach, or remove it from the esophagus.

Barrett's esophagus is a premalignant condition. Its malignant sequela, oesophagogastric junctional adenocarcinoma, has a mortality rate of over 85%. The risk of developing esophageal adenocarcinoma in people who have Barrett's esophagus has been estimated to be 6–7 per 1000 person-years, however a cohort study of 11,028 patients from Denmark published in 2011 showed an incidence of only 1.2 per 1000 person-years (5.1 per 1000 person-years in patients with dysplasia, 1.0 per 1000 person-years in patients without dysplasia). The relative risk of esophageal adenocarcinoma is approximately 10 in those with Barret's esophagus, compared to the general population. Most patients with esophageal carcinoma survive less than one year.

Barrett's esophagus occurs due to chronic inflammation. The principal cause of the chronic inflammation is gastroesophageal reflux disease, GERD (UK: GORD). In this disease, acidic stomach, bile, and small intestine and pancreatic contents cause damage to the cells of the lower esophagus. Recently, bile acids were shown to be able to induce intestinal differentiation, in gastroesophageal junction cells, through inhibition of the epidermal growth factor receptor (EGFR) and the protein kinase enzyme Akt. This results in the eventual up-regulation of the p50 subunit of protein complex NF-κB ("NFKB1"), and ultimately activation of the homeobox gene "CDX2", which is responsible for the expression of intestinal enzymes such as guanylate cyclase 2C. This mechanism also explains the selection of HER2/neu (also called ERBB2) and the overexpressing (lineage-addicted) cancer cells during the process of carcinogenesis, and the efficacy of targeted therapy against the Her-2 receptor with trastuzumab (Herceptin) in the treatment of adenocarcinomas at the gastroesophageal junction.

Researchers are unable to predict who with heartburn will develop Barrett's esophagus. While no relationship exists between the severity of heartburn and the development of Barrett's esophagus, a relationship does exist between chronic heartburn and the development of Barrett's esophagus. Sometimes, people with Barrett's esophagus have no heartburn symptoms at all. In rare cases, damage to the esophagus may be caused by swallowing a corrosive substance such as lye.

Patients with esophageal candidiasis present with odynophagia, or painful swallowing. Longstanding esophageal candidiasis can result in weight loss. There is often concomittant thrush.

Some patients present with esophageal candidiasis as a first presentation of systemic candidiasis.

The current first-line treatment is fluconazole, 200 mg. on the first day, followed by daily dosing of 100 mg. for at least 21 days total. Treatment should continue for 14 days after relief of symptoms.

Other therapy options include:

- nystatin is not an effective treatment for esophageal candidiasis. It can be used as (swish, do not swallow) treatment for oral candidiasis that occurs with the use of asthma pumps.

- other oral triazoles, such as itraconazole

- caspofungin, used in refractory or systemic cases

- amphotericin, used in refractory or systemic cases

Esophageal rupture in Boerhaave syndrome is thought to be the result of a sudden rise in internal esophageal pressure produced during vomiting, as a result of neuromuscular incoordination causing failure of the cricopharyngeus muscle (a sphincter within the esophagus) to relax. As the intra-oesophageal pressure increases, the bolus within the oesophagus has nowhere to go superiorly (as the cricopharyngeus fails to relax) which causes the oesophagus to rupture. (this makes little sense and should be justified if true: the lesion is down, the cricopharyngeus is up). The syndrome is commonly associated with the consumption of excessive food and/or alcohol as well as eating disorders such as bulimia.

The most common anatomical location of the tear in Boerhaave syndrome is at left posterolateral wall of the lower third of the esophagus, 2–3 cm before the stomach.

Currently, the most common cause of esophageal perforation is iatrogenic. However, iatrogenic perforations, while still constituting a serious medical condition, are easier to treat and less prone to complications, particularly mediastinitis and sepsis. This is because they usually do not involve contamination of the mediastinum with gastric contents.

With the exception of a few case reports describing survival without surgery, the mortality of untreated Boerhaave syndrome is nearly 100%. Its treatment includes immediate antibiotic therapy to prevent mediastinitis and sepsis, surgical repair of the perforation, and if there is significant fluid loss it should be replaced with IV fluid therapy since oral rehydration is not possible. Even with early surgical intervention (within 24 hours) the risk of death is 25%.

Both sex are equally affected

Any age group can develop a parapheryngeal abscess but it is most commonly seen in children and adolescents. Adults who are immunocompromised are also at high risk.

Infection can occur from:

- Pharynx: acute and chronic infection of tonsil and adenoids

- Teeth: dental infection occurs from lower last molar tooth

- Ear: bezold abscess and petrositis

- Other space: infection of parotid retropharyngeal space

- External trauma: penetrating injuries of neck, injection of local anaesthetic

It is a commonly encountered otorhinolaryngological (ENT) emergency.

The number of new cases per year of peritonsillar abscess in the United States has been estimated approximately at 30 cases per 100,000 people. In a study in Northern Ireland, the number of new cases was 10 cases per 100,000 people per year.

In Denmark, the new number of new cases is higher and reaches 41 cases per 100,000 people per year. Younger children who develop a peritonsillar abscess are often immunocompromised and in them, the infection can cause airway obstruction.

The pus can be removed by a number of methods including needle aspiration, incision and drainage, and tonsillectomy.

Treatment can also be given while a patient is under anesthesia, but this is usually reserved for children or anxious patients. Tonsillectomy can be indicated if a patient has recurring peritonsillar abscesses or a history of tonsillitis. For patients with their first peritonsillar abscess most ENT-surgeons prefer to "wait and observe" before recommending tonsillectomy.

Hyoid bones fractures represent 0.002% of all fractures; they are rare because the hyoid bone is well-protected by its location in the neck behind the mandible and in front of the cervical spine, as well as its mobility. 91.3% of hyoid bone fractures occur in men.

Neck trauma, commonly by strangulation, athletic activities, and car accidents, is the cause of a hyoid bone fracture. Other causes include violent vomiting, gunshot wounds, and hanging.