Stroke or Transient Ischemic Attack (TIA): The sudden onset of tingling on one side of the body is a classic symptom of a stroke or TIA. This condition occurs when the blood supply to part of the brain is interrupted or reduced, preventing brain tissue from getting oxygen and nutrients.

Multiple Sclerosis: An autoimmune disease that affects the brain and spinal cord, leading to symptoms such as numbness, tingling, and weakness in various parts of the body, including one side.
Peripheral Neuropathy: Damage to the peripheral nerves can cause tingling sensations, often starting in the hands and feet but can affect one side of the body.
Migraine: Some types of migraines can cause neurological symptoms, including tingling or numbness on one side of the body, before or during the headache phase.

Spinal Cord Injury or Compression: Conditions such as herniated disks, spinal stenosis, or tumors can compress the spinal cord, leading to tingling, numbness, or weakness on one side of the body.
Brain Tumor: Although less common, a tumor in the brain can cause localized symptoms, including tingling on one side of the body, depending on its location.
Lyme Disease: In its later stages, Lyme disease can cause neurological symptoms, including numbness or tingling, especially if the central nervous system is involved.

Vitamin B12 Deficiency: Can cause neurological symptoms, including numbness or tingling in the hands and feet, though it's less likely to cause unilateral symptoms.
Sjögren's Syndrome: An autoimmune disorder that can affect the nerves, leading to tingling or numbness, among other symptoms.
Guillain-Barré Syndrome: A rare autoimmune disorder where the body's immune system mistakenly attacks part of its peripheral nervous system, which can lead to tingling and numbness, typically starting in the legs and ascending.