Tongue numbness, medically referred to as oral paresthesia, is a sensation characterized by tingling, prickling, or a complete loss of feeling in the tongue. Individuals often describe it as a “pins and needles” sensation, similar to a limb falling asleep. This phenomenon can affect a single part of the tongue or the entire surface. While this sensation is frequently temporary and harmless, it can occasionally indicate a more significant underlying health matter.
Everyday and Transient Causes
Many instances of tongue numbness are temporary and stem from common, non-serious factors. A frequent cause involves dental procedures, particularly those requiring local anesthetics such as lidocaine or articaine. These agents temporarily block nerve signals in the treated area, and as their effects wear off over a few hours, the tongue may experience residual numbness or tingling. This sensation typically resolves completely as the anesthetic is metabolized by the body.
Minor physical trauma to the tongue can also induce temporary numbness. This includes accidentally biting the tongue while chewing or experiencing burns from consuming hot foods or beverages. The heat or physical injury can momentarily disrupt the superficial nerve endings in the tongue’s papillae, leading to a localized sensation of numbness. Similarly, exposure to certain irritants, such as very spicy foods, can overload sensory receptors and cause a transient numbing effect. Some oral hygiene products may also temporarily irritate nerve endings, resulting in a similar sensation.
Nutritional Deficiencies and Systemic Conditions
Tongue numbness can sometimes point to deeper internal health issues, including certain nutritional deficiencies that impact nerve function. A notable example is a lack of vitamin B12, often associated with pernicious anemia. Vitamin B12 is crucial for maintaining the myelin sheath, a protective layer around nerve fibers, and its deficiency can lead to peripheral neuropathy, manifesting as numbness or tingling in various body parts, including the tongue. Other B vitamins, such as B1 (thiamine), B6 (pyridoxine), and B9 (folate), also play roles in nervous system health, and their insufficient levels can similarly contribute to sensory disturbances.
Beyond vitamin deficiencies, several systemic diseases can cause tongue numbness as a symptom. Diabetes, for instance, can lead to diabetic neuropathy, a form of nerve damage resulting from prolonged high blood sugar levels. This condition can affect nerves throughout the body, including those supplying sensation to the tongue.
Multiple Sclerosis (MS) is another neurological disorder where the immune system attacks the myelin sheaths of nerves in the brain and spinal cord; demyelination in areas that control tongue sensation can result in numbness. Furthermore, a stroke or a Transient Ischemic Attack (TIA), often referred to as a “mini-stroke,” can cause sudden onset numbness, which may affect one side of the tongue along with other facial or body parts, due to disrupted blood flow to the brain. Hypothyroidism, a condition where the thyroid gland does not produce enough hormones, can sometimes cause nerve compression or damage, leading to sensory changes like tongue numbness. Certain autoimmune conditions, such as Sjögren’s syndrome, primarily affect moisture-producing glands but can also lead to nerve involvement. Lupus, another autoimmune disease, can also cause neurological complications that manifest as sensory disturbances, including numbness in the tongue, through inflammation or damage to nerve tissues.
Medication Side Effects and Allergic Responses
Certain medications can have side effects that manifest as tongue numbness or altered sensation. Some antibiotics have been reported to cause peripheral neuropathy, which can include sensory disturbances in the tongue. Chemotherapy drugs, used to treat cancer, are well-known for their neurotoxic effects, often leading to chemotherapy-induced peripheral neuropathy that can cause numbness and tingling in the hands, feet, and sometimes the oral cavity, including the tongue. Medications for high blood pressure or certain anticonvulsants can also occasionally produce sensory changes as an adverse effect.
Acute allergic reactions represent another category of causes for tongue numbness. When an individual is exposed to an allergen, such as specific foods like tree nuts or shellfish, medications, or environmental triggers, the body’s immune response can lead to localized swelling and inflammation. This swelling, particularly in the mouth and throat, can compress nerves, resulting in a tingling or numb sensation in the tongue. In more severe allergic reactions, such as anaphylaxis, rapid swelling can occur in the mouth, tongue, or throat, leading to significant sensory changes and potentially affecting breathing.
When to Seek Professional Guidance
While many instances of tongue numbness are benign and resolve on their own, certain circumstances warrant consultation with a healthcare professional. It is advisable to seek medical guidance if the numbness persists for several days with no improvement, or if it progressively worsens over time. Similarly, the appearance of additional symptoms alongside tongue numbness should prompt medical evaluation.
These accompanying symptoms might include muscle weakness, changes in vision, difficulty speaking clearly, facial drooping, a severe headache, or problems with balance. Such combinations could indicate a neurological event or a more serious underlying condition. Sudden onset of significant tongue numbness, especially if it affects both sides without a clear, benign cause, is another reason to seek prompt medical attention. Any concern regarding the sensation, or if the numbness is affecting daily life abilities such as eating, drinking, or talking, also justifies a professional assessment.