Nocturnal leg cramps is a common disorder affecting up to 33% of people over 50 years old, especially in later life. Nocturnal leg cramps have a significant impact on quality of life, particularly sleep quality. The exact mechanism of this disorder is unknown, the cramps are probably caused by the abnormal excitability of the anterior horn cells or the intramuscular motor nerve terminals. Mechanical factors – tendon shortening in later life and immobility – may also contribute to cramps development. Nocturnal leg cramps are mostly idiopatic, however, other medical conditions, e.g side effects of some medications, several neurologic diseases and diabetes, are also linked to their development. Quinine is the only medication that has proven to modestly reduce the frequency and intensity of leg cramps. Because of its serious side effects, quinine should be prescribed for a short time. Leg muscle stretching exercises may have some effect on prevention and relieving of leg cramps.