What is d cause of numbness from head to foot?

Hyperventilation: This is a common cause and can include episodic chest pain, shortness of breath, racing heart, and sense of doom. See a doctor and have some basic tests. Breath holding exercises, relaxation therapies, yoga, biofeedback, and practice at heartmath.Com can help to reverse the problem. Calcium and b- vitamins might help. Avoid coffee. You might need to train your mind to control your body.