Chalie horse or the nocturnal leg cramp can be caused by reasons as simple as a new shoe or exercising in excess or the causes behind it could indicate a medical problem. The deficiency of electrolytes and potassium can cause cramps.

The other causes of Charlie horse are hormonal imbalance and vascular problem. It can also be caused by stomach flu accompanied by diarrhoea. Diabetes is also considered as the probable causes of Charlie horse. Certain medicines like diuretics and beta blockers can deplete the body of potassium and cause cramps. Extreme change in temperature, lack of supply of oxygen to muscles and keeping the same posture for long period can also cause cramps in legs. These are also seen during pregnancy by some women.