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Dilated Pupils

Dilated Pupils: Introduction

Dilated pupils occur when the pupils of the eyes increase in size. The pupils are commonly known as the round, black centers of the eyes. Dilation of the pupils is a normal response to low levels of light or darkness. This response helps a person to see better in situations of low light.

Excessively dilated pupils (mydriasis) or unequal pupils can be a sign or symptom of a wide variety of mild to serious diseases, disorders and conditions. Dilate pupils can be due to head trauma, malignancy, neurological conditions, poisonings, death, and the use of certain recreational drugs and therapeutic medications.

Dilated pupils or unequal pupils can be the result of such serious, potentially life-threatening neurological conditions, intracranial hematoma, ruptured brain aneurysm, hemorrhagic stroke, intracranial hemorrhage, high intracranial pressure or a brain tumor.

Dilated pupils that are fixed and do not respond to light are one sign of death.

Dilated pupils can also be a sign of a wide variety of plant poisonings or chemical poisonings. Dilated pupils can be due to black nightshade poisoning and toxic mushroom poisoning.

Dilated pupils also occur with the use of certain types of therapeutic medications, such as antihistamines and atropine eye drops or pills. Dilated pupils can also be a sign of illegal or recreational drug use, such as methamphetamine use, marijuana use, amphetamine use, LSD use. Dilated pupils can also be a sign of narcotic withdrawal and heroin withdrawal.

Depending on the underlying disease, disorder or condition that causes dilated pupils, it often occurs in conjunction with other symptoms, such as altered level of consciousness and coma. Complications of underlying disease, disorders and conditions that cause dilated or unequal pupils vary and can be serious and life-threatening. For more details about symptoms and complications, see symptoms of dilated pupils.

Diagnosing dilated pupils and its root cause begins with taking a thorough personal and family medical history, including symptoms, and completing a physical examination, including an eye exam and thorough neurological examination. An eye examination includes testing how the pupils respond to light and comparing the size and reactivity of the two pupils.

A neurological exam includes assessing a patient's level of consciousness, orientation, speech, verbal response to simple questions and ability to open eyes and follow simple commands. Simple bedside testing and assessment of the functioning of the eight cranial nerves is also performed.

Lab testing varies depending on the suspected underlying cause of dilated or unequal pupils. Blood tests may include arterial blood gases, complete blood count (CBC), glucose, electrolytes, blood urea nitrogen and creatinine, and drug screen and ethanol (alcohol) levels.

CT and MRI of the brain is done in suspected cases of head trauma, intracranial hematoma, ruptured brain aneurysm, hemorrhagic stroke, intracranial hemorrhage, high intracranial pressure, or a brain tumor. X-rays of the cerebral blood vessels, called cerebral angiography, may also be done if a developing brain aneurysm is suspected.

A diagnosis of a serious underlying cause of dilated pupils may be delayed because dilated pupils can be a late sign of a developing condition. For information on misdiagnosis, refer to misdiagnosis of dilated pupils.

Treatment of dilated pupils involves diagnosing and treating the underlying disease, disorder or condition that is causing it. Some conditions that cause dilated or unequal pupils, such as ruptured cerebral aneurysm may not have an optimal prognosis. For more information on treatment, refer to treatment of dilated pupils. ...more »

Dilated Pupils: Symptoms

Dilated pupils often occur with other symptoms which vary, depending on the underlying disease, disorder or condition that causes dilated pupils.

Symptoms that accompany dilated pupils or unequal pupils due to serious neurological conditions include altered level of consciousness, confusion, slurred speech, paralysis, headache, vomiting, severe weakness, incontinence ...more symptoms »

Dilated Pupils: Treatments

Treatment plans for dilated pupils are individualized depending on the underlying cause, the presence of coexisting diseases, the age and medical history of the patient, and other factors. Treatment generally involves a multifaceted plan that addresses the underlying cause, and minimizes the develoment of serious complications.

Hospitalization and intensive care are generally necessary ...more treatments »

Dilated Pupils: Misdiagnosis

Diagnosing the underlying cause of dilated pupils may be delayed because a dilated pupil can be a late sign of a critical condition, such as serious head trauma. Earlier symptoms include headache, confusion and vomiting. Dilated pupils and unequal pupils are a sign or symptom of many different conditions, so a thorough medical evaluation is needed to ensure an ...more misdiagnosis »

Symptoms of Dilated Pupils

Home Diagnostic Testing

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Wrongly Diagnosed with Dilated Pupils?

Causes of Dilated Pupils

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Dilated Pupils: Undiagnosed Conditions

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Dilated Pupils: Research Doctors & Specialists

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Dilated Pupils: Animations

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Definitions of Dilated Pupils:

Dilation of pupils to greater than 6 mm combined with failure of the pupils to constrict when stimulated with light. This condition may occur due to injury of the pupillary fibers in the oculomotor nerve, in acute angle-closure glaucoma, and in ADIE SYNDROME. - (Source - Diseases Database)

Related Dilated Pupils Info

More information about Dilated Pupils

  1. Dilated Pupils: Introduction
  2. Symptoms
  3. Causes
  4. Treatments
  5. Misdiagnosis
  6. Home Testing

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