Restless leg syndrome one cause of nocturnal cramps
Dear Dr. Roach: Would you discuss causes of nocturnal leg cramps? I have exhausted all of the common remedies without success. — R.S., M.D.
Answer: Leg cramps are common. They begin suddenly and affect the calf or foot with an involuntary, painful contraction. The muscle becomes tight and hard, and it is relieved by stretching the muscle, especially by standing or walking. The most common cause of leg cramps at night is “idiopathic,” which is Greek for “one’s own disease,” meaning we do not know the cause. There are some risk factors, such as having flat feet and being sedentary.
However, people with nocturnal leg cramps should be evaluated for common conditions that cause symptoms of leg pain, cramping or discomfort. Restless leg syndrome in particular can cause leg discomfort and involuntary movements. People with blockages in the arteries of the legs also might have pain and cramping, though these occur with movement rather than at rest in bed.
Other conditions that often are associated with nocturnal leg cramps include neurological diseases such as Parkinson’s; abnormalities in electrolytes, such as calcium, magnesium or sodium; and metabolic diseases, such as diabetes and hypothyroidism. Some medications appear to predispose a person to leg cramps, especially some asthma medicines (like salmeterol, a component of Advair) and some types of diuretics, such as hydrochlorothiazide.
I know you have tried common remedies, but let me include them here anyway. Stretch the muscles several times daily, including in the evening and just before bed. To do this, keep the heel flat while leaning forward for 10 to 20 seconds. Hamstring stretches also may be helpful in preventing cramps. Shoes with more support in the heel (ask for a “long-countered shoe”) are better. Avoid alcohol, caffeine and dehydration.
Some of the less common remedies may still be effective. These include vitamin B complex, iron for those with iron deficiency, and possibly magnesium supplements.