Numbness, loss of sensation or abnormal sensation in any part of the body is medically referred to as paresthesia. The sensation of a 'limb falling asleep' may be due to the cause when the supply of blood to a part of the body gets cut off. This may be a result of sitting in one posture for long stretches of time. Recurring episodes of a partial or complete loss of sensation, however, are usually associated with an underlying neurological disorder. Though any part of the body could get affected by this condition, people usually experience numbness and tingling in hands or lower extremities.
Facial numbness and tingling, which is also called facial paresthesia, is not as common as loss of sensation in hands or feet. Such abnormal sensations on the face are usually attributed to irritation of the nerves located in this region. If the facial nerve that controls the muscles located on the sides of the face gets pinched or injured or the nerve function gets affected due to a medical condition, one may suffer from numbness and tingling on the face.
What Causes Numbness and Tingling on Face?
Though isolated or transient episodes of facial numbness may not really be a cause of serious concern, recurring episodes are indicative of a neurological problem that must be diagnosed and treated at the earliest. Given below are the neurological conditions that may lead to numbness on face.
The trigeminal nerve is main sensory nerve of the face that sends impulses from the brain to the skin. This nerve also sends impulses to the muscles of mastication. If this nerve gets pinched or compressed, one may suffer from a partial or complete loss of sensation on one's face. Trigeminal neuralgia is a medical condition associated with this nerve which is characterized by severe facial pain. This neuropathic disorder may be caused due to multiple sclerosis. Compression of this nerve by a tumor or a swollen blood vessel could also lead to this condition. The episodes of severe facial pain may be preceded by facial paresthesia.
Besides trigeminal neuralgia, abnormal sensations may also be experienced when one is down with herpes zoster. Herpes zoster, which is commonly known as shingles, is caused when the varicella zoster virus gets reactivated. This virus is also responsible for causing chickenpox. Once infected this virus lies in dormant stage within the body, with no symptoms. It may get reactivated due to severe stress or other conditions. It usually follows along a nerve path. If it travels along the trigeminal nerve, one is likely to experience numbness, tingling and formation of blisters along the nerve path.
This is another medical condition that could lead to numbness and tingling on face. It is associated with the inflammation of the seventh cranial nerve that controls the movement of the muscles of the face. It is believed that viral infections such as meningitis or shingles or conditions such as Lyme's disease, sarcoidosis or a middle ear infection may cause inflammation of the facial nerves, which in turn, may lead to numbness in the face. Since the nerve that controls the facial muscles is affected, the affected side of the face may feel numb and might droop. Symptoms such as drooling, eye problems, or pain behind one ear may be experienced.
Loss of sensation or abnormal sensations could occur as a result of a stroke or a transient ischemic attack. A stroke occurs when the blood flow to a part of the brain is affected due to rupturing of a blood vessel or blockage of a blood vessel in the brain. These sensations may be a direct result of death of the brain cells or abnormal electrical activity caused by lack of oxygen in the brain. Transient ischemic attack or mini-stroke, is caused due to temporary disruption in the blood flow, and doesn't involve death of brain cells. Both stroke and mini-stroke can lead to numbness on one side of the face.
This is an autoimmune condition wherein the immune system is unable to differentiate the body's own cells from the foreign cells. As a result, the immune cells start targeting the nerve cells and damage myelin, which is the protective covering around the nerve fibers. Damage to myelin makes the nerve fibers susceptible to damage, which in turn, may give rise to numbness or loss of sensation along with a variety of distressing symptoms.
Besides the aforementioned conditions, vitamin B12 deficiency, peripheral neuropathy, diabetes or hyperventilation could also cause facial paresthesia. Treatment of numbness on face would depend on the condition that triggered the numbness. Since facial paresthesia could be caused due to a wide range of reasons, it's important that the underlying cause be ascertained. Once the underlying cause is ascertained, suitable treatment options can be suggested by the doctor.