Tingling in the hands is known by the more accurate term paresthesia , but paresthesia can refer to tingling, burning, or numbness that also occurs in other extremities. There are numerous causes of paresthesia in the hands. Some of these are temporary and benign and others are very serious. If the tingling is present most of the time or occurs regularly, people experiencing it should see a doctor to determine the cause.
Some of the simplest causes can be the sensation of the hand waking up after "falling asleep". If pressure is put on a nerve that is connected to one or both hands, they can go numb. When the pressure is removed, the hand begins to wake up and may have a pins-and-needles sensation. Some people may notice tingling in their hands all day if they wear shirts that constrain the arms. Once this restriction ends, the tingling usually goes away.
Other causes of tingling in the hand can be the result of more constant pressure on the nerves. Conditions like carpal tunnel syndrome can create numbness or pins and needles in the thumb, index, and middle fingers, and other repetitive motion injuries to the wrist can cause the little finger and ring finger to feel numb or tingly.
Injuries or inflammation in the arm or spine can compress or damage the nerves relatively permanently, or at least until the injury heals. This could cause tingling in one or both hands, depending on the location of the compressed or damaged nerve. A direct injury to the hand, such as a fracture or broken bone in the hand or wrist, can also cause pins-and-needles sensations, although it usually causes pain as well.
Paresthesia of the hands may be the result of conditions that are not due to injury. It can be caused by things like vitamin B12 deficiency or by conditions like multiple sclerosis. People who are in the midst of a heart attack may notice tingling in one or both hands.
A host of other conditions can have hand tingling as a side effect. These include migraines, Guillain-Barré syndrome, all forms of diabetes, stroke, and Sjogren's syndrome. Low thyroid levels (hypothyroidism) or very low calcium levels could also be a potential cause.
Some medications can cause tingling in the hand and these may include some over-the-counter antihistamines and medications to treat migraines. If paresthesia seems to occur when taking a medication, check to see if it is a listed side effect, or call a pharmacist or doctor for more information. Some substances cause hands to tingle, and one of the most concerning is lead exposure. Lead poisoning easily leads to paresthesia and this symptom that occurs in children who may have been exposed to lead should not be ignored.
In total, there can be more than 50 causes of tingling in the hands and more than 100 medications that can cause it. Because the causes are so varied, persistent paresthesia deserves medical attention. Its presence may not be threatening, but it can also indicate life-threatening conditions such as stroke or heart attack.