Meyahealth
HomeGeneticsConditionDopamine beta-hydroxylase deficiency
Back to Condition
Dopamine beta-hydroxylase deficiency
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Condition

Dopamine Beta-Hydroxylase Deficiency

Dopamine beta-hydroxylase deficiency is an ultra-rare autonomic disorder caused by the inability to produce norepinephrine, resulting in severe blood pressure dysregulation and exercise intolerance.

Overview

Dopamine beta-hydroxylase deficiency is a rare genetic disorder of the autonomic nervous system, the regulatory network responsible for managing involuntary bodily functions, including core body temperature and blood pressure. The clinical features stem from a profound deficiency of norepinephrine, a vital chemical messenger (neurotransmitter) that transmits signals across the autonomic nervous system.

Signs and Symptoms

Although underlying physiological signs can be present during infancy, many individuals are not formally diagnosed until adolescence, when clinical manifestations often become more pronounced.

Infancy and Early Childhood

  • Drooping eyelids (ptosis)
  • Consistently low blood pressure (hypotension)
  • Recurrent episodes of vomiting and dehydration
  • Decreased body temperature (hypothermia)
  • Low blood glucose levels (hypoglycemia), frequently resulting in hospitalizations

Adolescence and Adulthood

  • Severe drop in blood pressure upon standing (orthostatic hypotension), which can trigger dizziness, blurred vision, or fainting (syncope)
  • Pronounced exercise intolerance due to the inability to maintain hemodynamic stability
  • Persistent nasal congestion
  • Inability to stand upright for extended periods
  • Retrograde ejaculation, where semen travels backward into the bladder during ejaculation

Without intervention, symptoms typically escalate during adolescence; however, clinical features may improve substantially with appropriate medical therapy.

Causes and Genetics

The condition is caused by variants (mutations) in the DBH gene. The DBH gene encodes the enzyme dopamine beta-hydroxylase, which is responsible for catalyzing the conversion of dopamine into norepinephrine.

Mutations in this gene eliminate or drastically disrupt the function of the dopamine beta-hydroxylase enzyme. As a consequence, dopamine cannot be converted into norepinephrine, depriving the autonomic nervous system of the neurotransmitter necessary to adjust vascular tone, sustain blood pressure, and maintain proper autonomic function.

Inheritance

Dopamine beta-hydroxylase deficiency follows an autosomal recessive inheritance pattern. An individual must inherit two altered copies of the DBH gene (one from each parent) to develop the condition. Parents of an affected child typically carry one altered copy as asymptomatic carriers, experiencing no signs or symptoms of the disorder themselves.

Prevalence

This condition is exceptionally rare. As of 2021, approximately 25 individuals with dopamine beta-hydroxylase deficiency have been documented in scientific and clinical literature.

Alternative Names

  • DBH deficiency
  • Dopamine β-hydroxylase deficiency
  • Orthostatic hypotension 1

Frequently Asked Questions

Treatment focuses on managing symptoms rather than curing the enzyme deficiency. Common interventions include the use of midodrine, a medication that raises blood pressure, and fludrocortisone, which helps the body retain salt and water to increase blood volume. Some patients may also benefit from dopamine agonists or other supportive therapies. Regular monitoring by a specialist in autonomic disorders is essential to adjust medications and prevent complications like fainting or falls.
Yes, dopamine beta-hydroxylase deficiency is inherited in an autosomal recessive pattern. This means a person must inherit two mutated copies of the DBH gene, one from each parent, to develop the condition. Parents who are carriers typically do not show symptoms but have a 25 percent chance with each pregnancy of having a child with the disorder. Genetic counseling is recommended for families considering having more children to understand the risks and available testing options.
Patients are advised to stand up slowly to prevent dizziness and fainting, and to wear compression stockings to help maintain venous return. Dietary changes, such as increasing salt and fluid intake, can help raise baseline blood pressure. Regarding exercise, high-intensity activities that cause rapid heart rate increases should be avoided; instead, low-impact activities like swimming or stationary cycling are often better tolerated because they allow for better hemodynamic stability and reduce the risk of sudden blood pressure crashes.
Diagnosis usually begins with a clinical evaluation of autonomic symptoms such as severe orthostatic hypotension and exercise intolerance. Doctors will order genetic testing to identify variants in the DBH gene, which is the definitive diagnostic method. Additionally, biochemical tests measuring norepinephrine levels in the blood or urine can support the diagnosis, as these levels will be significantly low or undetectable, while dopamine levels may be elevated due to the blocked conversion process.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

Meyahealth

Ⓒ 2026. All rights reserved by MEYA

About UsTerms & PolicyFAQ