What is SIADH?

SIADH is the syndrome of inappropriate antidiuretic hormone secretion. It is a rare condition in which the body makes too much antidiuretic hormone (ADH), resulting in water retention in the body and decreased sodium levels in the blood.
Antidiuretic hormone (ADH), also called vasopressin, is produced in the brain by the hypothalamus gland. The hormone is then stored in and released by the pituitary gland. ADH hormone helps kidneys conserve the correct amount of water in the body, hence regulating the way the body eliminates and conserves water. When ADH is produced in excess, it results in SIADH. SIADH can be due to a problem in the hypothalamus or other causes and triggers. It can occur at any age and is seen more often in children.
SIADH makes it difficult for the body to eliminate water. Water retention in the body leads to decreased levels of electrolytes, such as sodium. The condition of low sodium levels in the body is called hyponatremia. Hyponatremia is responsible for many of the symptoms of SIADH and can result in serious complications. Treatment is usually conservative, involving limiting fluid intake and medication to reduce water retention and ADH levels. Treatment of the underlying cause of SIADH is also required.What causes SIADH?
Several conditions can trigger abnormal ADH production, including
- Infection and inflammation of the brain
- Bleeding in or around the brain
- Psychosis
- Injury to the head
- Hydrocephalus (fluid accumulation in the brain)
- Guillain-Barre syndrome (a condition in which the immune system attacks the nerves)
- Multiple sclerosis (a disease in which the immune system damages the protective covering of nerves)
- Generalized infections, such as HIV and Rocky Mountain spotted fever
- Cancers of the lung or gastrointestinal or genitourinary tract lymphoma, sarcoma
- Lung infection, such as pneumonia
- Asthma
- Cystic fibrosis (an inherited life-threatening disorder that damages the lungs and digestive system)
- Certain medications and anesthesia
- Sarcoidosis
- Hereditary factors
What are the signs and symptoms of SIADH?
SIADH makes it difficult for the body to release excess water and as a result there is accumulation of fluid in the body and hyponatremia (low sodium levels). Fluid retention and hyponatremia are responsible for many of the signs and symptoms of SIADH. The symptoms may be mild and vague at first and may go unnoticed. However, the symptoms can become more severe. In severe cases, the following signs and symptoms may be present
- Irritability and restlessness
- Loss of appetite
- Muscle cramps
- Muscle weakness
- Nausea and vomiting
- Mental confusion
- Memory problems
- Headache
- Changes in personality
- Depression
- Tremors
- Hallucinations (experiencing things that are not present)
- Seizures
- Stupor (a serious mental state where people don't respond to conversation and only to physical stimulation, such as to pain or rubbing on their chest)
- Coma
How is SIADH diagnosed?
The doctor will ask for the medical history and conduct a physical examination of the patient. A blood test to check the ADH levels and electrolytes levels would be done and a urine sample would also be taken. Imaging studies (such as magnetic resonance imaging or MRI) may be done to rule out bleeding or tumors in the brain.
What is the treatment and prognosis for SIADH?
The treatment involves limiting fluid intake to avoid further buildup. Medications to reduce water retention (such as diuretics) and inhibit ADH may include Lasix (furosemide) and Demeclocycline. The underlying medical conditions triggering SIADH would also be treated. The prognosis will depend on the cause of SIADH. If untreated, it can lead to respiratory failure, coma and death.
StatPearls
Top What Causes SIADH Related Articles
Asthma
Asthma is a condition in which hyperreactive airways constrict and result in symptoms like wheezing, coughing, and shortness of breath. Causes of asthma include genetics, environmental factors, personal history of allergies, and other factors. Asthma is diagnosed by a physician based on a patient's family history and results from lung function tests and other exams. Inhaled corticosteroids (ICS) and long-acting bronchodilators (LABAs) are used in the treatment of asthma. Generally, the prognosis for a patient with asthma is good. Exposure to allergens found on farms may protect against asthma symptoms.What Is Asthma? Symptoms, Causes, and Treatments
What is asthma? What is the main cause of asthma? Learn information about asthma, a chronic disease of the bronchiole tubes. Discover information about asthma attacks, complications of asthma, and how to control an asthma attack.Can Stress Cause Multiple Sclerosis (MS)?
Multiple sclerosis (MS) results when your immune system attacks the cells of the brain and spinal cord. It is an autoimmune disease, a condition in which the body's immune system is misdirected and attacks its own cells. Stress can make it difficult for a person to manage MS symptoms. Regular exercise and mindful eating have been found to control the stress levels and overall health of people with MS.Can You Fully Recover From Guillain-Barre Syndrome?
Guillain-Barre syndrome (GBS) may last between 14 and 30 days and you may slowly recuperate from it. Usually, recovery takes 6 to 12 months, but for some people it could take up to 3 years. GBS is rare and affects fewer than 4,000 people in the United States each year.HIV Early Signs and Stages
HIV (human immunodeficiency virus) weakens your immune system. Some people with HIV don’t have any symptoms, but those that do may experience mononucleosis-like or flu-like symptoms. There are 3 stages of HIV.25 Hormone Imbalance Symptoms and Signs
Hormone imbalance involves changes in estrogen, progesterone, and other hormone levels. Hormonal imbalance in women may cause symptoms like weight gain, hot flashes, fatigue, and acne. Hormonal changes happen in menopause and at other times. Women with hormone imbalances can seek treatment from medications like triptans and SSRIs.Human Immunodeficiency Virus (HIV)
HIV (human immunodeficiency virus) infection left untreated causes AIDS (acquired immunodeficiency syndrome). The human immunodeficiency virus (HIV) is a type of virus called a retrovirus, which can infect humans when it comes in contact with tissues that line the vagina, anal area, mouth, or eyes, or through a break in the skin. HIV infection is generally a slowly progressive disease in which the virus is present throughout the body at all stages of the disease. Three stages of HIV infection have been described. The initial stage of infection (primary infection), which occurs within weeks of acquiring the virus, often is characterized by the flu- or mono-like illness that generally resolves within weeks. The stage of chronic asymptomatic infection (meaning a long duration of infection without symptoms) lasts an average of eight to 10 years without treatment. The stage of symptomatic infection, in which the body's immune (or defense) system has been suppressed and complications have developed, is called the acquired immunodeficiency syndrome (AIDS). The symptoms are caused by the complications of AIDS, which include one or more unusual infections or cancers, severe loss of weight, and intellectual deterioration (called dementia). When HIV grows (that is, by reproducing itself), it acquires the ability to change (mutate) its own structure. These mutations enable the virus to become resistant to previously effective drug therapy. The goals of drug therapy are to prevent damage to the immune system by the HIV virus and to halt or delay the progress of the infection to symptomatic disease. Therapy for HIV includes combinations of drugs that decrease the growth of the virus to such an extent that the treatment prevents or markedly delays the development of viral resistance to the drugs. The best combination of drugs for HIV are those that effectively suppress viral replication in the blood and also are well tolerated and simple to take so that people can take the medications consistently without missing doses.Multiple Sclerosis (MS) Symptoms and Treatments
Multiple sclerosis (MS) symptoms vary from person to person and can last for days to months without periods of remission. Symptoms of MS include sexual problems and problems with the bowel, bladder, eyes, muscles, speech, swallowing, brain, and nervous system. The early symptoms and signs of multiple sclerosis usually start between ages 20-40. MS in children, teens, and those over age 40 is rare. Treatment options for multiple sclerosis vary depending on the type and severity of symptoms. Medications may be prescribed to manage MS symptoms.Multiple Sclerosis (MS)
Multiple sclerosis or MS is an autoimmune disorder in which brain and spinal cord nerve cells become demyelinated. This damage results in symptoms that may include numbness, weakness, vertigo, paralysis, and involuntary muscle contractions. Different forms of MS can follow variable courses from relatively benign to life-threatening. MS is treated with disease-modifying therapies. Some MS symptoms can be treated with medications.Multiple Sclerosis (MS) Early Warning Signs and Types
Multiple sclerosis (MS) can be thought of as an immune-mediated inflammatory process involving different areas of the central nervous system (CNS) at various points in time. Early warning signs and symptoms of MS in children, teens, and adults are similar; however, children and teens with pediatric also may have seizures and a complete lack of energy. Adults with MS do not have these signs and symptoms. Other signs and symptoms of MS include inflammation of the optic nerve (optic neuritis), changes in vision, Wiping or having tissues around the eye and moving the eye may be painful, and double vision. There are four types of MS, relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), primary progressive MS (PPMS), and progressive relapsing MD (PRMS).MS Quiz
Multiple Sclerosis is a debilitating neurological condition. Take the MS Quiz to test your knowledge of the causes, symptoms, risks and treatments.MS Slideshow
MS is an autoimmune disease that attacks the nerves of the central nervous system. Learn about multiple sclerosis (MS) causes, symptoms, and treatment, along with diagnosis and life expectancy.Sarcoidosis
Sarcoidosis, a disease resulting from chronic inflammation, causes small lumps (granulomas) to develop in a wide range of body tissues and can appear in almost any body organ. However, sarcoidosis most often starts in the lungs or lymph nodes.Sarcoidosis Causes
The research to reveal the exact cause of sarcoidosis is unknown. Certain inherited genes make it more likely for a person to develop sarcoidosis.What Is the Role of the Hypothalamus?
The hypothalamus is a part of the midbrain. An important function of the hypothalamus is to link the nervous system to the endocrine (hormonal) system through the pituitary gland. The hypothalamus is considered the regulator of all hormonal functions in the body.