Symptoms

A cramp pain typically lasts a few minutes. In some cases, it lasts just seconds; however, in some cases, it lasts up to 10 minutes. The severity of the pain varies. The muscle may remain tender for up to 24 hours after a leg cramp. Leg cramps usually occur when you are resting – most commonly at night when in bed. They are often called night cramps. They may wake you. It can become a distressing condition if your sleep is regularly disturbed.

Causes

Unknown cause (idiopathic leg cramps)

In most cases, the cause is not known. One theory is that cramps occur when a muscle that is already in a shortened position is stimulated to contract. As the muscle is already shortened, contracting further may cause the muscle to go into spasm. This commonly happens at night in bed, as the natural position we lie in is with the knees slightly bent (flexed) and with feet pointing slightly downwards. In this position, the calf muscle is relatively shortened and may be prone to cramps. This theory explains why stretching exercises may cure the problem.

Secondary causes

In some cases, the cramps may be a symptom of another problem. For example:

• Some medicines can cause cramps as a side-effect, or make cramps occur more often. These include: ‘water’ tablets called thiazide diuretics and loop diuretics, nifedipine, cimetidine, salbutamol statins, terbutaline, lithium, penicillamine and phenothiazines (prochlorperazine, perphenazine, chlorpromazine).
• Over-exertion of muscles.
• Lack of fluid in the body (dehydration).
• Conditions that cause alterations in the balance of salts in the bloodstream (such as a high or low sodium or potassium level).
• Some people who have kidney (renal) dialysis have leg cramps.
• Pregnancy – usually in the later stages.
• An untreated underactive thyroid gland.
• Peripheral arterial disease. In this condition, there is a narrowing of the leg arteries which causes poor circulation.
• Excess alcohol.
• Some uncommon disorders of nerves.
• Rare causes include ‘scarring’ of the liver (cirrhosis), lead poisoning and an inflammatory condition called sarcoidosis.

Positions that prevent the calf muscle from shortening when you are asleep may help. The following are not proven treatments (from research); however, some experts believe that they help to prevent cramps:

• Using a pillow to prop your feet up in bed while sleeping on your back.
• Hanging the feet over the end of the bed while sleeping on your front.
• Keeping blankets loose at the foot of the bed to prevent toes and feet from pointing downwards during sleep.

Your Doctor examines you to try to find out the reason for your cramps.

They will suggest a treatment depending on the cause.

This might be:

• stretching exercises
• quinine tablets if your cramps are very bad and exercise has not helped

Quinine is not suitable for everyone. Your Doctor will discuss potential risks and side effects with you.

Stretching and massaging the affected muscle can usually relieve an attack of cramp. Most cramps soon ease off. Painkillers are not usually helpful as they do not act quickly enough. However, a painkiller such as paracetamol may help to ease muscle discomfort and tenderness that sometimes persist for up to 24 hours after a cramp has gone.

Leg cramps are common and most common in the calf muscles. They can occur in any muscle group. The cause is not known in most cases. However, some medications and diseases sometimes cause leg cramps. Regular calf stretching exercises may prevent leg cramps. Quinine tablets may be advised as a last resort if you have cramps regularly.