What is causing the paralysis on one side of my body?

The cause of paralysis on one side of the body, known as hemiplegia, can vary widely and may be due to different underlying conditions or factors. Determining the specific cause often involves a thorough medical evaluation, including physical examinations, imaging studies, and sometimes laboratory tests. Here are some common causes of hemiplegia:


Ischemic strokes, caused by a blocked blood vessel, or hemorrhagic strokes, caused by bleeding in the brain, are common causes of hemiplegia. Strokes result in damage to the brain tissue, leading to motor and sensory deficits on one side of the body.

Traumatic Brain Injury (TBI):

Head injuries resulting from accidents, falls, or other traumatic events can lead to hemiplegia if the injury affects the motor areas of the brain.

Spinal Cord Injury:

Trauma or damage to the spinal cord, often due to accidents or falls, can result in paralysis on one side of the body or in specific regions.

Brain Tumor:

Tumors in the brain, depending on their location and size, can exert pressure on the motor areas, causing hemiplegia.

Multiple Sclerosis (MS):

MS is an autoimmune condition in which the immune system attacks the protective covering of nerve fibers. This can lead to disruptions in nerve signals and result in hemiplegia.

Guillain-Barré Syndrome:

This autoimmune disorder affects the peripheral nerves and can lead to weakness or paralysis. Hemiplegia is possible in severe cases.

Cerebral Palsy:

Cerebral palsy is a group of neurological disorders that affect movement and coordination, often stemming from brain damage before or during birth.


Infections affecting the brain, such as encephalitis or meningitis, can cause inflammation and damage, leading to hemiplegia.

Vascular Disorders:

Conditions like arteriovenous malformations (AVMs) or vascular malformations can disrupt blood flow and cause strokes, resulting in hemiplegia.

Metabolic Disorders:

Some metabolic conditions, such as hyperglycemia or electrolyte imbalances, can lead to neurological symptoms, including hemiplegia.

Genetic Disorders:

Certain genetic disorders, such as hereditary spastic paraplegia, can cause progressive weakness and paralysis, often starting on one side of the body.

Functional Neurological Disorder (FND):

FND is a condition in which neurological symptoms, including weakness or paralysis, are not explained by structural damage. It is believed to be related to disruptions in the nervous system’s functioning.

It’s crucial to seek prompt medical attention if you or someone else experiences sudden or unexplained paralysis. Diagnosis and appropriate treatment depend on identifying the underlying cause. A neurologist or healthcare professional will conduct a thorough assessment, which may include neurological examinations, imaging studies (such as CT scans or MRI), and other diagnostic tests to determine the cause of hemiplegia.