Such pins and needles sensations in various parts of the body are called Paresthesias.
The different types of abnormal sensations that are experienced include tingling, pricking, or numbness. They may occur in a patch of skin or over a whole limb.
Paresthesias occur due to a sensation in the nerves. This can occur due to diabetes, thyroid disorders, stress, anxiety, aging, etc. You should first check up with your doctor to check for these conditions, specially diabetes and hypothyroidism.
There are various ways to treat Paresthesias. This also depends on the cause. In general, Maintaining optimum weight, proper diet, vitamin supplements, exercise, treating stress and depression will help in reducing the symptoms. You should try to achieve this at home. You should also take Vitamin B and Vitamin E supplements which are available at all pharmacies. You should also go for regular exercise.
If these steps do not help, you need to consult a neurologist for this. You may need tests like Nerve conduction tests to diagnose your condition.
You can look up here: http://en.wikipedia.org/wiki/Numbness
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