What is the definition of Agranulocytosis?

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In simple terms, the definition of agranulocytosis is that it is a rare but very serious side effect of some medications including common mental illness treatments, such as certain antipsychotic medications, mood-stabilizing drugs, antidepressants, and anxiolytics. These are prescriptions that are often used to treat mental health issues like depression, anxiety and borderline personality disorder.


Induced by these drugs, agranulocytosis is blood disorder that is marked by a sudden and rapid reduction of white blood cells, also known as granulocytes. Granulocytes are critical to your immune system's strength, so if you are suffering from agranulocytosis, you are at a higher risk of getting an infection. Because of the weakened immune system, you may more easily contract illnesses caused by bacteria that your body could normally fend off. This can make even common and relatively harmless bacteria extremely dangerous for you. 

When Does Agranulocytosis Occur?

Agranulocytosis typically appears about 3-4 weeks after beginning a new medication or after switching to a higher dosage of your usual medicine, but it can occur at any time, particularly with certain drugs. The psychiatric medications with the greatest risk of agranulocytosis are Clozaril (clozapine), a drug used to treat schizophrenia, and Tegretol (carbamazepine), a medication used to control seizures and nerve pain.When starting a new medication or changing your dosage, be sure to consult with your doctor about agranulocytosis and other medicines you are taking.


What are the Symptoms of Agranulocytosis?

While the definition of agranulocytosis is fairly straight forward, the symptoms are very varied and complex. According to the National Organization of Rare Disorders, some of the early symptoms include the same symptoms as common infections, such as chills, fever, and fatigue.

As the white blood cell account decreases, ulcers can appear in the mouth and throat and you may experience difficulty swallowing. 

Who Does Agranulocytosis Impact?

Agranulocytosis affects both men and women equally. Those with already compromised immune systems are at a higher risk for contracting this disease as well as patients who are taking cancer or thyroid medications

How is it Diagnosed?

Agranulocytosis is usually diagnosed when you visit the doctor complaining of infection symptoms. The doctor will review your medical history and the medications you are taking; if you are taking one of the medications known to be associated with this disease, blood tests will be ordered to determine your blood cell levels

Is Agranulocytosis Treatable?

While agranulocytosis is a serious condition that is life threatening and requires immediate treatment, it is also rare (e.g., affects less than 1% of individuals taking medications associated with even the greatest risk of this side effect). Upon diagnosis, your doctor will take you off of the prescriptions associated with this disease and antibiotics may be prescribed. More developed cases will require hospitalization. 

If caught early, agranulocytosis is treatable, but it becomes harder to treat the further along it is.

If you are on any medications commonly associated with agranulocytosis, it's important to talk to your doctor about the risks and keep him informed about how you're feeling and if there are any symptoms. 


Flanagan RJ, Dunk L. “Haematological Toxicity of Drugs Used In Psychiatry.” Human Psychopharmacology: Clinical and Experimental. 23:27-41, 2008.

National Association of Rare Disorders. Agranulocytosis. http://rarediseases.org/rare-diseases/agranulocytosis-acquired/ , 2007. 

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